Location: Running from Wallsend Northumberland to Solway Firth, Cumberland Date completed: c. 122 AD Designers/builders: Built to the orders of Hadrian, Emperor of Rome Function: Defensive fortification, customs control

It's 1,700 years ago that the Romans left Britain. Yet so solidly did they build that mementoes of their presence are to be found all over Britain: in straight roads, in the remains of luxurious villas, in forts and in place names. 

Perhaps the most striking reminder of Roman genius is to be found in the far north of England, where much of Hadrian's Wall still stands. Built with hard labour and primitive technology by Romans and locals, it still has the power to awe. Despite depredations through the ages by local farmers looking for stone to build barns and walls, substantial parts of the wall still stand. As the name suggests, Hadrian's Wall was constructed in the reign of the Roman emperor Hadrian around 120 AD. It runs from Wallsend to the Solway Firth, a distance of 73 miles (117.5 km or 75 Roman miles). It does not actually mark the border between England and Scotland - it is entirely in England - in some places it is 70 miles from the Border. The dimensions and construction of the Wall depended on its location and the materials available. Squared stone was used for the section east of the River Irthing (the border between Northumberland and Cumbria, about 16 miles (25 km) east of Carlisle). Here the Wall was around 16 ft to 20 ft (5-6 m) high and 10 ft (3 m) broad. West of the river, the wall was originally made of turf, later replaced by stone. Every Roman mile, small towers, called milecastles, were built on the wall, while larger forts were located every 3-7 miles (5-11 km).  There were 17 of these forts, several of which remain in some form. Vindolanda is a fort that predates the wall by forty years and has been a rich source of evidence of daily life at the time. This is mainly due to the Vindolanda Tablets. These are thin postcard-size pieces of wood, with scripts written in ink. They include an invitation to a birthday party from Claudia Severa to Sulpicia Lepidina, together with military reports, tradesmen's correspondence and letters to troops.