Simon Calder: Let's hear it for Latin American railway engineers

Just what Dr Beeching didn't order, but what we need: a new age of the train. Air France has announced that it will do the decent thing and become Rail France, running ultra-high-speed trains between London and Paris.

Except when fire intervenes, Eurostar runs a good operation between St Pancras and Gare du Nord. But since the new high-speed link from London to the Channel opened last November, passenger numbers have risen by nearly a fifth. Flights between Heathrow and Paris Charles de Gaulle, once the busiest international air route in the world, have withered to the point where the few remaining services are aimed at connecting passengers. (One reason so many travellers this weekend will find themselves stranded on the wrong side of the Channel by the tunnel fire is the lack of airborne alternatives.)

Meanwhile, average fares on Eurostar have risen. For my trip to Toulouse last week, easyJet easily undercut the rail fare from London via Paris. If the train-that-thinks-it's-a-plane starts running through the Channel Tunnel within two years, as hoped, Eurostar will have to raise its game and lower its fares.

German Railways, too, is considering a St Pancras to Cologne service, which will raise the interesting prospect of travelling from Kidderminster to Koblenz entirely in the care of Deutsche Bahn; the German operator already owns Chiltern Trains, which runs between Worcestershire and Marylebone station in London. Sit back in the comfort of an ICE seat – far superior to Eurostar's ageing rolling stock – and let the zug take the strain.

But before you drift off on the Thames-Rhine Express, let me tell you about far more dramatic developments on the rails in South America.

The editorial notes at the start of Thomas Cook's Overseas Timetable rarely demonstrate excitement. But the new edition (£13.50) trumpets: "Big news from Ecuador!" In normal times, the Andean nation astride the equator barely rates two full pages in the authoritative compilation of global locomotion. There are evidently some unusual features of Ecuadorian trains: between El Progreso to San Lorenzo, better turn up in force: "Minimum of 10 passengers required" says a footnote.

As with no-frills flying in Britain, everyone aged over two is classed as an adult. But unlike low-cost airlines – and, for that matter, most low-cost train operators – all Ecuadorian rail services "carry passengers on the roof". And these are not fare-dodgers or second-class citizens: the compiler notes "two classes of accommodation, coach and roof, with fares being identical". Even if you're three years old.

The main schedule covers trains from the capital to the coast, between Quito and the nation's second city of Guayaquil. This is one of the world's great rail journeys, at least in theory. It begins high in the Andes, spiriting travellers away from the friendly but rarefied sprawl of the capital, and through the corridor of fire – an avenue along the spine of the Andes flanked by volcanoes.

About halfway along, the challenge faced by the 19th-century railway builders becomes apparent. The line switchbacks down an Andean escarpment, eventually to be enveloped in the muggy, tropical caress of Ecuador's lowlands. After the austerity of the highlands, Guayaquil provides the warm, welcoming and colourful gateway to the Galapagos Islands ("Cargo/passenger service, every 15/17 days", since you ask).

Who wouldn't want a train trip like that? The trouble is, the schedule is full of holes. Rail buffs will be disappointed to learn that all services from the capital as far as Latacunga, 60 miles south, are suspended. A 75-mile gap between Latacunga and Riobamba has no trains at all. For the stretch to the vibrant market town of Alausi, operators have taken a leaf out of Britain's book by offering "bustitution" – a bus replacement service. Seek, though, Alausi's makeshift station (locate Carmita's beer shop, then look for a pair of rails), and you find the terminus for one of the great tourist train rides: the "Devil's Nose" line. But currently you have to return to the same scruffy patch of wasteland.

So why the excitement at the offices of Thomas Cook? Nothing short of resurrection of the shattered dreams of the railway builders. The entire line from Quito to Guayaquil is being reinstated. By January, the work should be complete. And there will be plenty of room: "Two new trains – with roof-riding accommodation – are in the final stages of construction." If everything goes to plan (which it never, ever does in Latin America), the Quito-Guayaquil journey will, on a good day, take all day to cover roughly the same distance as London to Paris. But I know which I would prefer.