Travel: This road once led to Rome

In Norfolk, it is still possible to drive along an ancient route staggeringly rich in Roman remains.

The A140 is a road lined by ghosts. Today it is a trunk route between Norwich and Ipswich. Two thousand years ago it was the road between the Roman town of Venta Icenorum and Camulodunum or, as it's better known today, Colchester. Fifty-five years ago it was the road north from the Eighth Air Force base at Thorpe Abbotts to the fleshpots of Norwich.

Like most Roman regional capitals, Venta was an artificial foundation, designed to exploit tribal identities. The name means "market-place of the Iceni". The towns were endowed with Roman public buildings, such as a forum; the plan was that the natives would flock to the town to buy Roman goodies and get sucked into Roman life.

This was normally successful, but not in Norfolk, which was a backwater in Roman times. When the town was walled in the 200s AD those walls enclosed a smaller area than the original foundation. Venta was shrinking. Perhaps memories of Boudicca's revolt, when she burst out of Norfolk at the head of the Iceni to fight the Romans in the year 60, kept Roman traders away.

When the Saxons moved into the area in the fifth century, they settled where Norwich is now. Venta crumbled, and returned to nature. The ruins lie close to the village of Caistor St Edmund, about a mile and a half east of the A140 just south of Norwich. The turning is off the roundabout where the A140 meets Norwich's ring road, the A47.

Go south through the village of Caistor, pass the church and just beyond you'll see a small parking area. From here a footpath leads around the ruined walls of Roman Venta. On the west side a crumbling bastion, made of ragstone and tile, still stands proud of the tattered earthen banks that mark the walls. It's hard to believe that this was once a thriving town with houses, government buildings and public baths.

One of the mysteries of Roman Britain is how this relatively poor area - villas, for instance, are few and far between - has yielded some of the greatest treasures not just of Britain but of the whole Roman world. It was at Hoxne (pronounced "Hoxxen"), near Diss, that Eric Lawes found a fabulous late Roman treasure in 1992. The carefully buried hoard (dating to the year 408 or later - the date of the last coin found) included not only a magnificent series of silver spoons, jewellery, and silver pepperpots, but also nearly 15,000 gold and silver coins.

Why was this flabbergasting quantity of wealth buried near the old Roman road? In those days, five gold coins would pay a soldier for a year. At the time Roman Britain was coming to an end. With institutions crumbling, rebels revolting and barbarians battering the shore defences, there was good reason to bury valuables. Already for more than a century East Anglia had been defended by a series of forts around the coast. Burgh Castle, not far away near Great Yarmouth, is one of the best preserved.

Some of the Hoxne spoons carry the name of Aurelius Ursicinus, but no one knows who he was. Perhaps he and his family had travelled across Britain from their home and stashed their savings in what was then a remote place. Perhaps the treasure had already been requistioned by officials and was to be used to pay off barbarians.

We'll never know. There's nothing to see here now, but the treasure is all on display in the new Romano-British gallery at the British Museum in London along with the two other great Roman treasures of East Anglia: Thetford and Mildenhall.

Half a century ago this part of England became a huge aircraft carrier, confronting another threat from across the North Sea. East Anglia was the main concentration of bases for the American Eighth Air Force, active here between 1942 and 1945. Thorpe Abbotts, close to Dickleburgh on the A140 and a stone's throw from Hoxne, was home to the 100th Bombardment Group, known to its members and history as the Bloody Hundredth. On their 306 missions the men of this unit suffered some of the heaviest losses of the whole Eighth Air Force. They are commemorated today by the 100th Bombardment Group museum, which is to be found in and around the restored control tower.

There are displays of workshops and tools, recovered engines from crashed bombers, uniforms, models and mementoes. The airfield is mostly gone now, but the huge expanse of runways and taxi-ways have left their mark in the vast cleared areas between the trees.

Stand on the top of the control tower and look out across the weed-strewn taxi-way and beyond to the bales of hay that sit in the middle of the runway. This was where the base officers craned their necks to scan the sky and count the Boeing B-17 Flying Fortress bombers as they returned. The losses were sometimes colossal. On 17 August 1943 the Bloody Hundredth participated in one of the most ambitious air raids of the war to date, when they bombed Regensburg. Of the 21 aircraft that left from here that day, nine were lost.

To relax, the crews would leap into trucks and hurtle to Norwich up the A140 for a few days' leave. Here they crowded along Norwich's cobbled streets, bewildered by the sheer antiquity of one of Britain's finest medieval cities, appalled by the warm beer, and captivated by the women who were mesmerised by American ways. The Romans and the Eighth Air Force have become part of a national myth. But the A140 still serves as it has always done, lined by the ghosts of Britain's wars, ancient and modern.

The Hoxne treasure is on permanent exhibition in London at the British Museum (0171-636 1555). Nearest Tube: Russell Square. Open daily (Sundays afternoons only). Free. An excellent booklet by Roger Bland and Catherine Johns (pounds 4.95) covers the story of the find and has first-class illustrations. The Castle Museum in Norwich has finds from Caistor (01603 223624). Roman Caistor St Edmund is open at any reasonable time (OS Ref. TG 230035, sheet 134). So is the fort of Burgh Castle (OS Ref. TG 475046, sheet 134), three miles west of Great Yarmouth. The 100th Bomb Group museum (01379 740708) at Thorpe Abbotts is signposted from Dickleburgh on the A140. Open all year at the weekend (10am-5pm, 4.30pm between October and April), and on Wednesdays from May to September (10am-5pm). Free