The wall runs from the west of Cumbria to Wallsend

It is the first time in 1,600 years the 84 miles from Bowness-on-Solway in Cumbria to Wallsend, Tyneside, can be walked in full.

The Countryside Agency has developed 30 miles of new rights of way to follow the wall's path, along with new gates, footbridges and stiles.

Parts of the wall have always been open to the public but large parts had crumbled and the complete right of way had disappeared.

It was the most heavily fortified border anywhere in the Roman Empire Jim Crow Newcastle University Why did Hadrian build his wall?

But �6m later, it has been restored - apart from in a couple of places where the wall is buried under a road - and many parts now have disabled access.

Countryside Agency chief executive Richard Wakeford has spent the last week walking along the World Heritage Site.

He has predicted that 20,000 people a year would walk the route by 2006.

He added: "It's good news for holidaymakers, dedicated walkers and people who want a refreshing day out, and it is good news for local people who live and work along the wall."

ROUTE OF THE TRAIL Walking the wall

David Taylor, owner of the 15th century Centre of Britain hotel in Haltwhistle, Northumberland, claimed the path would have as big an impact as the Romans had on the local economy.

He said: "The trail is the best thing to happen in this area since Hadrian's Wall was built.

"It has the potential to revolutionise the local economy."

The wall itself was 80 Roman miles (73 miles) when first built. Hadrian is thought to have ordered its construction when he visited Britain in AD 122 on a tour of his empire.

It took six years to build and involved three legions of soldiers from Rome plus auxiliary troops from around the empire.

The wall, which marked the northern frontier of the empire beyond which lay the "barbarian" tribes of what is now Scotland, was well defended with look-out posts, forts and deep ditches.

"It was the most heavily fortified border anywhere in the Roman Empire," said Jim Crow, senior lecturer in archaeology at Newcastle University.

"It shows that the Romans were concerned about security to the south of the wall as well as to the north," he told BBC News Online.