The odd man and the mountain: Is Jonathan Pratt Britain's most successful mountaineer? A storm is raging among the climbing elite about this outsider's claim to have conquered the world's two highest peaks

THE ALPINE CLUB is home to the elders of the British mountaineering world. Founded in 1857, it was first housed in panelled premises in London's South Audley Street, adorned with such mementoes as the rusting oxygen cylinders carried by club members during their pioneering attempts on Everest in the 1920s, and the ice-axe abandoned by the Oxford undergraduate Sandy Irvine, when he and George Mallory made their doomed bid for the summit in 1924.

Three years ago, the Alpine Club moved to more austere premises in a narrow Victorian street near the Barbican, where its members still hold lectures and committee meetings with the old aplomb. Tonight they have gathered once again, a largely middle-aged group, predominantly men, many in suits and including several veterans of the 1953 Everest expedition, to hear their latest guest describe his exploits. In the past, the most celebrated figures of the mountaineering world, from Edward Whymper to Edmund Hillary, have stood before the Alpine Club, but tonight's speaker does not quite have the same resonance. His name is Jonathan Pratt.

A short, lean man, with ginger hair, dressed casually in an open-necked shirt and jumper, Pratt is standing against the wall of the Alpine Club bar with a friend. It soon becomes apparent that he is not quite at home in these august surroundings. It is not just that Pratt appears ill at ease - it is the first time he has lectured about his climbs - but that few among the Alpine Club members even recognise him.

'Which one is he?' asks a member standing at the club bar.

'I think he's the one on the right.'

It is unfortunate that Britain's mountaineering establishment should fail to recognise Pratt, since he is, by definition, Britain's most successful mountaineer. In 1992, then virtually unheard of in mountaineering circles, he climbed Everest. This was a bravura ascent, accomplished without the usual panoply of equipment and porters, but it was not unique: Pratt was the 11th British climber to stand on the world's highest summit, with Doug Scott and Chris Bonington among his predecessors. A year later, however, Pratt elevated himself to the highest rank by adding K2, the world's second highest mountain - just 237m lower than Everest - to his list of ascents. Both Bonington and Scott have attempted K2 and failed. The only two British climbers to have succeeded, Julie Tullis and Alan Rouse, both died during their descents. Pratt is thus the only British climber to have reached K2's summit and survived; and the only British climber to have scaled the world's two highest peaks.

There is, however, an important caveat. Each time Pratt's ascent of K2 is mentioned, his detractors add the following words: 'Or so he says.' For a significant coterie of the mountaineering community disputes Pratt's claim to have climbed K2; and their doubts have reached members of Pratt's audience at the Alpine Club. Among mountaineers, where one's word is taken as one's bond, this is a sensitive matter. The unavoidable implication is that Pratt is a liar and a cheat.

Pratt rejects this accusation: 'They weren't there,' he says, of those who contest his account. Yet he is not his own best witness. When he comes to the lectern at the Alpine Club, to be greeted with only modest applause, his presentation of his account of his alleged ascent of K2 can best be described as amateurish. In comparison with the fluent, hi-tech approach of professional mountaineers such as Bonington and Scott, Pratt speaks haltingly and illustrates his talk with a limited selection of slides, some projected the wrong way round. Nor is there any shot of the moment when he and his partner, the American Dan Mazur, stood on the summit - considered a sine qua non of mountaineering accounts.

If he did climb K2, Pratt has an extraordinary tale to relate. In marked contrast to many of today's more media-friendly mountaineers, he has mounted most of his expeditions at minimal cost, without publicity. Until K2 he had barely been mentioned in climbing magazines, and even now few in the climbing world know anything about him. Nor, before now, has he ever given an interview to a national newspaper.

I first talked to him at his parents' home, in Shenfield, Essex, where he stays for the three months or so of the year when he is not away climbing. Aged 35 and unmarried, he is a graduate of the Royal School of Mines in South Kensington. Although he now counts himself a full-time mountaineer, none of the sponsorship deals or publishing contracts which abound in modern mountaineering has ever come his way; instead, he finances his expeditions from short-term mining work and his savings from a lucrative spell of employment in the US during the 1980s. And during our interview he showed himself less adept at expressing himself than the Boningtons and Scotts, mostly supplying terse one-liners which were almost parodies of masculine understatement. 'I'm not very good at this,' he admitted.

Pratt agrees that his story is one of an outsider. But is he, in short, an outsider who has lied to gain status in the climbing world? Or one whom the climbing world - for whatever motives - has been reluctant to accept?

PERHAPS the most implausible detail about Jonathan Pratt is that he comes from Essex. It is not merely the predictable jokes about Essex man but the fact that Essex is irredeemably flat. His father is a retired architect, his mother a former Royal Navy officer, and it was they who first took him and his younger brother hill-walking on family holidays in Scotland.

In another contrast with today's mountaineering elite, schooled on Britain's crags from an early age, Pratt did not take up climbing until he was 22. At eight he was sent to board at Felsted, a minor public school where his main sport was hockey and where he developed several important characteristics: on the positive side, independence, self-reliance and a tolerance for hardship; on the negative, a limited ability to express his emotions.

Ironically, it was Pratt's work as a mining engineer which led to his induction into climbing. After qualifying in 1979, he went to work at a copper mine in New Mexico. In 1981 he started hiking in the desert landscape of the South- west United States, then began climbing on its red granite and sandstone buttes and spires. 'I thought, 'This is the thing for me.' '

By then he had become friendly with a fellow British engineering graduate, Chris Haggett, and in 1986 the pair gave up work in order to spend five years travelling and climbing in the world's principal ranges. Funded by their savings - Pratt says he earned five times as much in the US as he would have in the UK - they headed for South America, working their way from the northern Andes to Patagonia. Haggett thought Pratt 'very determined, although you don't see that by just talking to him. He paced himself well and had a high degree of control. He's also modest. He's not going to blow his own trumpet. The challenge is for him and he does things for himself.'

They made several important ascents on the peaks of Peru's Cordillera Blanca, including the notorious south face of Chacaraju. Haggett found Pratt withdrawn and introverted at times - on summits they limited their celebrations to a stoical handshake. But they did unfurl a Union Jack, which Pratt always carried.

By 1989, despite eight years of climbing, Pratt had still done nothing to bring himself to the notice of the mountaineering world. Indeed, he himself had no way of judging his progress, although he was pleasantly surprised when he compared the speed of his ascents with other people's. 'I seemed to be climbing a lot faster than anyone else.' As well as South America, he had climbed in California, Scotland and the Alps. Yet his name had never appeared in the meticulously recorded data of ascents in the climbing magazines. And there now ensued an apparent hiatus in his career which was to fuel the subsequent suspicions against him.

When Pratt made his ascents of Everest and K2, he had no public history of climbing at that level: to his detractors, his claims thus appeared even more unlikely. Pratt offers a simple but potentially embarrassing explanation: from 1989 to 1991, he says, he was undertaking a series of unauthorised ascents in the Himalayas. He did so to avoid the fees and regulations imposed by the Himalayan countries - India, Nepal, Pakistan and China - which require climbers to buy permits costing up to pounds 6,600. Instead, to save money and avoid bureaucracy, Pratt slipped into the countries and headed for the mountains incognito. By his account, Pratt climbed a dozen substantial peaks in this period, most higher than 6,000m - and did so alone. Chris Haggett had been due to climb with him, but pulled out of the trip with weeks to go when he received an irresistible job offer from a company in Reading. 'By then,' says Pratt, 'it was far too late to find anyone else.'

With conventional mountaineering, you have a partner to hold you on a rope should you fall; there is no such safeguard in solo climbing. When you are climbing alone, one slip may prove fatal, and even a minor mishap such as a twisted ankle can have disastrous consequences. It thus calls for the utmost self-

reliance and confidence. But Pratt had already 'soloed' several climbs in the US. 'I wasn't worried. It wasn't new for me.'

Understandably, he remains guarded about this period. Although he listed the mountains he had climbed, he asked me not to publish their names, since this could prejudice his chances of returning to the countries concerned. 'It would be hard for them to prove I ever did it,' he says. 'But if it's written up, you are pleading guilty.'

Pratt's most spectacular ascent was of a mountain of around 7,800m which the British were the first to climb in the 1950s - and which no British team had climbed since. Pratt was alone on the mountain for 28 days and at one point was trapped by a storm in his tent at 6,500m for nine days. 'You have to worry there,' he concedes. 'You know you have to climb out. The snow was very deep and you think, if something goes wrong with the tent or anything - that's it.' Perhaps most remarkably, Pratt effectively climbed the mountain twice. Since he had no porters, he had to make a 'double carry' - taking up half his equipment, dumping it on the mountainside and returning for the other half. His strongest memory of the summit day is of the 'incredible wind' on the final stretch. 'Then, just as I got to the top, the wind cleared.'

Pratt acknowledges that there is a difficulty about his ascents during this period, namely that he has no witnesses. At the time, he says, it was not important whether the climbing world knew of his achievements. Now that his climbing record is at issue, however, there is compelling evidence to support his accounts. Back in Reading, Chris Haggett received a series of long, hand-written postcards and letters from Pratt detailing his ascents and also revealing an unsuspected side of the hitherto withdrawn mountaineer. 'It was as if he had just come off the mountain and was eager to tell someone what he had done,' Haggett says. 'They described the risks and dangers and how he had overcome them. They also described his achievements with a certain amount of pride.'

HAVING climbed a mountain of just under 8,000m, Pratt resolved to surpass that mark. It is a critical watershed, taking climbers into the realms of the 14 mountains above that height - such as Annapurna, Kangchenjunga and Nanga Parbat - and presenting a new scale of problems, not least the hazards of climbing at high altitude. Pratt's first goal was to climb K2, which he describes as the 'the mountaineer's mountain, the most challenging of the 8,000m peaks'. In fact, the first one he attempted was the highest of all.

Pratt was in Kathmandu when he heard that a mountaineering agent, In Wilderness Trekking, had a spare permit for Everest. 'I hadn't even thought about doing it,' Pratt says, but the chance seemed too good to miss. There was no question of climbing Everest without permission - it is far too public a place - and so Pratt paid pounds 1,300 for a share of the permit. He reckons the total cost of the expedition was pounds 1,600 - far less than most Everest expeditions, which can cost up to pounds 33,000 per person.

Since Pratt had made his previous Himalayan ascents alone, he saw no reason not to do so on Everest. He hired just two porters for the week-long trek through Nepal to the Everest base camp by the Khumbu glacier, where he pitched his tent among those of the dozen other expeditions attempting Everest that year. Again making double carries, he ferried his equipment up the route pioneered by the British in 1953 and used by most expeditions since: up the sheer Lhotse Face to the South Col - one of the most barren places on Earth, and launch-point for the summit 900m above.

Pratt was in a buoyant mood when he embarked on his first attempt. But he was stricken with diarrhoea on the Lhotse Face and was forced to retreat. A week later, he returned to the South Col, where he teamed up with a British climber, Mark Jennings. But their summit bid was defeated by a raging wind which threatened to hurl them into the air. Even now, Pratt has regrets about turning back: 'Perhaps by myself I'd have pushed harder,' he says.

By now, Pratt regarded Everest as something to be seen through. Back in Kathmandu he met a Chilean team with a permit for the spring of 1992 and paid pounds 1,300 to join them. The British climber Steve Bell, a member of a British Services expedition attempting Everest's south-west face, met Pratt in base camp. He recalls Pratt as 'a little unusual - outside the normal mould of British mountaineers. He kept himself to himself. I had never heard of him before, and when I heard he was attempting Everest I thought, 'He hasn't got a hope.' ' Bell also remembers that Pratt had arrived with a Chilean expedition 'and with a Czech girlfriend'. The Czech girlfriend was in fact Dina Sterbvola, a climber hoping to make the first female ascent for her country. Pratt ended up rescuing her when she collapsed from exhaustion on the fixed ropes leading to Camp Three on the Lhotse Face. After helping her down he returned to the South Col alone and spent two days sheltering from storms, brewing drinks in his tent to counter the lethal dehydration caused by high altitude. It was still snowing on the third morning, but Pratt felt he could wait no longer: 'It was now or never.'

Most other climbers then waiting on the South Col judged the conditions too bad, but as he headed for the foot of the South-east Ridge, Pratt was joined by the leader of the Chilean expedition, Mauricio Purto, and the highly experienced Sherpa, Ang Rita. Luck was with them. As they headed up the ridge, the weather cleared and other climbers began to follow. Since Pratt's account of climbing Everest has also been called into doubt, it is worth pointing out that he reached the summit in the company of no fewer than 17 other climbers, and was photographed, wearing just a shirt and climbing jacket, among the scrum of mountaineers at the top. 'It was a brilliant day,' he says.

WITH Everest under his belt, Pratt turned back to his original objective of K2. First climbed by Italians in 1954, it remained an awesome challenge, rising in one 3,000m sweep from the surrounding glaciers at the end of the eight-day trek through north-east Pakistan. By 1992 there had been 395 ascents of Everest and 110 deaths; the figures for K2 stood at 83 and 28 respectively. K2's standard route, the Abruzzi Ridge, is considered more difficult and dangerous than its equivalent on Everest, the South Col route. In 1986, 13 climbers had been killed on the mountain, including the Britons Julie Tullis and Alan Rouse. Despite 26 attempts, there had been no ascents since.

This time there was no question of a solo climb. Pratt joined an international expedition planning an attempt via the Abruzzi Ridge, in the summer of 1992. It included a Russian contingent whom he met in Kathmandu that spring and who offered him a place for pounds 2,000. On the mountain Pratt teamed up with an American, Dan Mazur, whom he had met on Everest in 1991. Like Pratt, Mazur, who works as a building contractor in Montana, was regarded as something of a loner in US climbing circles. Pratt enjoyed his company: 'He is very jovial, always seeing the bright side, always laughing.' Mazur found Pratt 'a rather austere person, a bit of an ascetic, someone who lived simply and liked to pursue his dreams.'

Pratt and Mazur made two determined attempts, twice reaching around 8,000m. At the end of August, as the rest of the expedition was packing up, they tried again, reaching 8,250m. Pratt felt confident and wanted to go on, but Mazur feared frostbite and insisted on turning back. Again Pratt had regrets. 'Afterwards I thought, why didn't I just keep going for the top alone?'

The pair began planning a fresh attempt even before they left Pakistan. This time they decided to attempt K2's West Ridge, which had been climbed only once before, in 1981. They also decided that their best chance lay in organising their own expedition. This meant that for the first time Pratt had to deal with the ruling circles of British mountaineering. The encounter was to prove a bruising one, leaving Pratt convinced that the mountaineering establishment was unwilling to provide help for outsiders, while he was accused of paranoia - or, as one Alpine Club patrician puts it, of being 'chippy'.

Pratt and Mazur recruited their team mostly among friends and friends of friends, selecting nine other climbers, none of them known in the higher echelons of the mountaineering world. They also had to finance the expedition. They estimated that it would cost around pounds 50,000, and so each climber was asked to pay pounds 4,000. They raised another pounds 1,000 for the expedition funds by organising a trekking party to the K2 base camp. This left a shortfall of several thousand pounds, and Pratt decided to apply for some of the grants which are available to assist British expeditions.

There are two principal mountaineering bodies in Britain that dispense grants. The first is the Mount Everest Foundation, which awards grants from the proceeds of the 1953 Everest ascent. The second is the British Mountaineering Council, which is funded by the Sports Council. It so happened that two members of the key committees at the MEF and BMC were also members of a second British expedition then planning to climb K2. One was the expedition leader, Roger Payne, a respected full-time official of the BMC. The second was Alan Hinkes, a professional mountaineer known in the climbing world as robust, ambitious and outspoken. Payne and Hinkes sat on both the MEF's screening committee and the BMC's international committee, which award the grants. It also happened that, like Pratt, Payne had applied for grants for his expedition. The short version of what ensued is that a) Pratt was turned down by both the MEF and the BMC and b) Payne received grants worth about pounds 2,000.

Pratt was angered by the committees' decisions. 'We were making a direct challenge to the BMC expedition,' he says, 'and that was the problem.' MEF officials insist that Pratt's application was turned down because it was poorly prepared and presented. In a letter to High, official magazine of the BMC, the MEF secretary, Bill Ruthven, and the chairman of the MEF's screening committee, Bob Pettigrew, pointed out that Pratt himself had not attended the hearing. 'Two rather less experienced members of the team turned up; they were extremely vague about many aspects of the expedition, being unable to answer questions put to them.' They insist that it was this 'dearth of information', and not 'any possible prejudice against a group of climbers who were not named', that was decisive. (Ruthven also points out that Payne and Hinkes withdrew from the MEF committee hearing when their own application was being considered.)

Pratt concedes that his application was 'a mess'. Because he was climbing in Africa at the time, a fellow team-member, Jonathan Wakefield, agreed to appear at the MEF hearing, held at the Royal Geographical Society headquarters on 16 March 1993. Wakefield, a detective with the Metropolitan Police, then dropped out, leaving two other expedition members to deputise. Bill Ruthven confirms that the two substitutes were quite unable to answer the committee's questions. 'The two guys that came were absolute - to use that word - prats,' Ruthven says. 'What could we do but turn him down?'

One of the substitutes, Andy Collins, the expedition doctor, takes a different view. Dr Collins agrees that some questions caught him unawares. 'What made it harder was that Roger Payne and Alan Hinkes were both sitting on the committee. I felt we answered their questions as fairly as we could. But I felt that they had made up their mind that there was something deeply wrong and that the team was a bunch of jokers.'

What particularly irked Pratt was to receive a one-sentence letter from the MEF. 'The management committee decided at its recent meeting that it would be unable to give either a grant or approval to your forthcoming expedition,' it declared. 'They didn't even say sorry,'

says Pratt. As for the refusal even to approve Pratt's expedition, only four out of 53 expeditions that year suffered the same fate. Shortly after the MEF decision, the BMC also refused Pratt a grant.

In a further bid for support, Pratt asked climbing manufacturers and retailers for sponsorship or equipment. Here, too, there was a poignant contrast in the fortunes of the two teams. Payne's expedition received around pounds 20,000 from Eastern Electricity (in return for which they helped oversee the installation of two village water-supply schemes in Pakistan) and equipment from the manufacturers Berghaus, for whom Hinkes acted as a consultant. Berghaus also issued bullish press releases about the team's preparations. Pratt's only success came when two manufacturers, Vango and VauDe, each supplied two tents, on condition that he returned them afterwards.

Pratt was thus in combative mood when he arrived at the K2 base camp among the jumbled moraine of the Godwin-Austen Glacier at the end of June 1993. Beside Payne's team, around half a dozen international expeditions were attempting K2, and all were camped on a well-established site known as the Strip. Pratt pointedly selected a site some 20 minutes' walk away across the moraine. While this was closer to the start of the West Ridge, Pratt adds: 'We didn't want to be with those guys - we wanted to be on our own.'

The separation contributed to a competitive edge between the two British teams. 'With the BMC sitting over there, they felt and I think we felt, to a lesser extent, we've got to beat these buggers,' Pratt says. Certainly some of his remarks - described by a fellow team-member as 'harmless banter' - got through to Payne. 'They were very pompous about the difficulties of their route and doing just about everything to wind people up,' Payne says.

Neither Payne nor Hinkes, in turn, made any secret of his view. 'The general air seemed to be that we were a load of bungling amateurs,' says Wakefield, who visited Payne's camp several times. There were few reciprocal visits, but when Payne's fellow expedition member Victor Saunders called at Pratt's camp, he found its occupants 'perfectly reasonable and pleasant'. Saunders adds: 'I didn't have any preconceptions about them, as the rest of my team seemed to.'

If there was a race between the two groups, it was Pratt's team that forged ahead. The West Ridge is a harder route than the Abruzzi, following a long series of shelves and gullies, and culminating in an intimidating rising traverse from the West Ridge on to the mountain's South Ridge, with a sheer drop of almost 3,000m to the glacier, before the final stretch to the summit. Pratt planned to follow the conventional approach of establishing camps, fixing safety ropes and ferrying supplies to around 8,200m. From there the lead climbers would launch out for the summit.

Despite interruptions from the weather, the team made steady, if slow progress through July. Yet K2 continued to exact its toll. Wakefield and a colleague narrowly survived an avalanche, and a French climber, Etienne Fine, had to be evacuated from the mountain at night after developing pulmonary oedema. There was a gradual attrition of other members, from frostbite and other ailments, and it took until mid-August - rather behind schedule - for the expedition to establish Camp 6 at 8,200m, poised for the summit bid.

Payne's team, meanwhile, had been faring far less well. They were discouraged by the deaths of five climbers on the Abruzzi Ridge that summer, and the weather was unpropitious too - somehow the wind seemed stronger than on the West Ridge. The leading pair reached a high point of only 7,600m, 1,000m below the summit. Then, in mid-August, Payne and his team headed home.

At this point, however, most of Pratt's expedition packed up to go home too - some because of injuries, others because they had run out of time and had to get back to their jobs. The only two to remain were Pratt and Mazur - and from this juncture they are the sole witnesses to what ensued. After resting at base camp, they returned to the mountain on 29 August, taking three days to reach Camp 6, where they prepared for their summit bid. That 1 September dawned fine, but as they set off they could see lenticular clouds, an omen of bad weather, hovering over the summit. They climbed a series of steps and ledges, followed by a snowfield and a steep gully. Then came a second snowfield which seemed liable to avalanche, but they crossed it without mishap.

By now the wind was strengthening and they were enveloped in cloud. They were finding the climbing harder than expected, particularly the last pitch at around 8,400m, which took them on to the South Ridge. Here they were heartened at finding a length of rope which they presumed was a relic from the 1981 expedition. But night was approaching, and by 8pm, save for a few fitful glimpses of the moon through the racing clouds, it was pitch-dark.

With 100m left to climb, Pratt and Mazur stopped in the lee of a boulder that offered some protection from the gathering storm. It was a decisive moment. Usually, in such circumstances, mountaineers either bivouac for the night or turn back. Only briefly, says Pratt, did they consider turning back. To bivouac for the night would have been risky, since they were carrying neither a tent nor oxygen. The only other option was to continue, with just their head-torches to illuminate the way. 'In the end,' says Pratt, 'we decided that every hour we spent up there would make it more dangerous. The weather seemed to be getting worse, so we thought, 'Just keep going, get to the top and get down.' '

Pratt and Mazur were relieved to find that the way ahead was relatively straightforward. When they reached a point where the rock of the ridge merged into the final stretch of snow, Pratt dumped his rucksack so that he could move forward unencumbered. 'There were quite a few false summits,' he says, 'and each time we thought, 'This has got to be it', and there was another one.' Finally, at around 11pm, recounts Mazur, 'we arrived at a high snow bulge and realised there was nowhere higher we could go.'

It was not, both men say, a moment for celebration - not even a handshake. The wind was shrieking around them and they felt weak from the immense effort, accentuated by the altitude; at that height, says Mazur, 'your head is reeling - every step is a major decision.' There was just one ritual to be performed: the summit photograph. Mazur had left his camera by the boulder where they had sheltered because it had no flash. As Pratt recalls, 'Dan said, 'Take the photograph' and I said, 'I don't have the camera.' I had left it in my rucksack.'

Pratt and Mazur reckon they spent barely a minute on the summit before heading back down. 'There was no reason to stay,' says Pratt. 'We couldn't see anything, and the longer we were there the worse it was going to get.' When Pratt reached his rucksack he took a photograph of Mazur: 'It could have been anywhere,' Pratt admits.

They were now in an appalling predicament, facing a descent from the world's second highest mountain at night and in a storm. After three painstaking days, they reached the safety of base camp, where only their liaison officer and cook remained to congratulate them. They celebrated by swigging a mouthful of whisky they found in a bottle left by their team.

DOUBTS OVER the ascent were voiced as soon as the news reached Britain. Alan Hinkes did so with least inhibition, even telling me, at the annual mountaineering trade fair in Harrogate at the end of September, that he doubted whether Pratt had climbed Everest the year before. Seven months on, as he prepared to depart for another attempt on K2, he remained just as sceptical, comparing Pratt's claim to that of Tomo Cesen, the Slovenian climber whose claim to have climbed the south face of Lhotse in 1990 is now widely disputed. 'You know,' says Hinkes, 'hanging on to the end till everybody had gone, and then saying you'd got up and not having any photographs and saying you'd battled through bad weather into the night.' It was all, Hinkes said, 'rather far-fetched', adding: 'That's just a personal opinion - but it's also the opinion of most of the other people who were there last year.'

In public, Roger Payne is more cautious than Hinkes, but he acknowledges the doubts that he has expressed. 'I've said that where people claim important ascents and report them to the media, my personal view is that they should be able to verify those claims by photographs or by the independent observations of other climbers at the time.' Payne tells the story, with an unmistakable sub-text, of another Slovenian climber who turned back 100m from the summit of K2 last year and admitted afterwards that he had failed.

Pratt's critics also believe that they have a smoking gun. It consists of a remark which Pratt is alleged to have made to the rest of his team as they prepared to depart. By this account, Pratt told them that he and Mazur planned to wait until everyone else had gone and then claim to have climbed K2.

The implication is stark. In the sceptics' scenario, Pratt and Mazur, having failed to climb K2, conspired to concoct an account of doing so. Their motivation, according to their detractors, stemmed from the rivalry between the two expeditions - or, as one sceptic put it, 'from some sort of competitive situation that existed in their own minds'.

There is, of course, an alternative scenario: that Pratt and Mazur did indeed climb K2. In this version, it is the same 'competitive situation' which has prompted the allegations that they lied. Payne and Hinkes deny this. 'It was not a matter of great concern to us what they were doing on the West Ridge,' says Payne. 'In fact, we wished them well.'

Pratt first became aware of the allegations when he read about them in High magazine early in 1994. He says that he and Mazur were not unduly surprised, as they had no summit photograph, nor had they followed the convention of leaving a memento at the summit for subsequent parties to find. 'We do not have 100 per cent proof,' Pratt concedes. He also agrees that he said that he and Mazur would wait until everyone else had gone and then pretend to climb K2. But he insists that this was a throwaway remark, and his colleague, Jonathan Wakefield, confirms that it was 'banter, a joke'.

In mountaineering history, there have certainly been other important ascents where the climber or climbers lacked 100 per cent proof and yet were believed. By the same token, there have been instances of climbers whose claimed ascents were widely disbelieved. One is the case alluded to by Alan Hinkes, that of Tomo Cesen. The other involved an Italian, Cesare Maestri, who claimed to have climbed Cerro Torre, a formidable granite spire in Patagonia, in 1959.

Yet there are significant differences between these cases and that of Pratt and Mazur. I interviewed both Maestri and Cesen. I found Maestri hostile and evasive, and he cut short our interview when it reached the disputed part of his ascent. Cesen at first replied readily to my faxed questions, but as the flaws and contradictions multiplied, he declined to respond any further. Pratt and Mazur, by contrast, have been open and co-operative. Pratt answered all my questions in a series of long interviews, and when I telephoned Mazur without warning in the US, he provided an account which matched Pratt's in all important respects. Although there were some minor discrepancies, these appeared more likely to result from imperfect memories of extreme events than from a flawed conspiracy.

The most significant difference is that both Cesen and Maestri were claiming to have completed solitary climbs. For Pratt and Mazur to have colluded in fabricating and sustaining a false account would require a breathtaking degree of joint duplicity.

All this is a question of judgement. But there is one crucial item of evidence to support Pratt and Mazur. It comes from one of the only two people to have climbed the West Ridge before Pratt and Mazur - the Pakistani mountaineer Nazir Sabir, who reached the summit with a Japanese climber in 1981.

Pratt and Mazur met Nazir in Islamabad after their climb. 'We talked for about three hours,' Nazir recalls. 'They are not the kind of people who really come out with their feelings. But they were very happy.'

Having heard their account, Nazir says he is 'very clear about their ascent - I think they have every right to claim they were on the summit.' What clinched it for Nazir was their account of finding a length of rope high on the route. Nazir reveals that he had abandoned this rope when it became stuck during an abseil on his descent. 'Things like that convinced me, and I really have no doubt.'

PRATT admits to finding it 'annoying' that his ascent of K2 has been in doubt. He is shortly to depart for an attempt on Gasherbrum, the world's 11th highest mountain and still awaiting a British ascent. He has not applied for an official grant, but has fared better in his bid for sponsorship; Vango has supplied him with nine tents (although it wants them back).

Pratt has been gratified to learn that among the mountaineering establishment there are now some important supporters of his cause. The mountaineer / journalist Stephen Venables, who climbed Everest in 1988, discussed Pratt's ascent with him at length. Before meeting him, he says, 'I had soaked up the general scepticism that was floating around. When I met him, his detail was very convincing. I'm certain he climbed it.' Venables concluded that Pratt was 'a bit of a maverick - in that he has challenged established assumptions about how to climb high mountains and what an individual can achieve.' Geoff Birtles, editor of High magazine, concluded that Pratt had achieved 'possibly the best high-altitude performance ever by a British climber'.

Perhaps the most significant convert was among Pratt's audience at the Alpine Club. When Pratt's talk ended, there was enthusiastic applause. One senior member who joined in was Lt-Col Tony Streather, a former Alpine Club president who took part in an epic attempt on K2 in 1953, and was also the patron of Roger Payne's expedition.

Streather had certainly been aware of the doubts over Pratt's ascent: 'Alan and Roger were the ones who were suspicious,' he confirms. But Streather found Pratt 'pretty convincing - they did some extraordinary things. I'm certainly not sceptical any more. I think they made it and good luck to them.'

Streather has just one regret. 'It's a pity,' he says of Jonathan Pratt, 'that he's got such an enormous chip.'-

(Photograph omitted)