Hadrian's Wall is a former defensive fortification of the Roman province of Britannia, begun in ADÂ 122 in the reign of the Emperor Hadrian. Running from Wallsend on the River Tyne in the east to Bowness-on-Solway in the west of what is now northern England, it was a stone wall with large ditches in front of it and behind it that crossed the whole width of the island. Soldiers were garrisoned along the line of the wall in large forts, smaller milecastles, and intervening turrets. In addition to the wall's defensive military role, its gates may have been customs posts.
A view of Hadrian's Wall showing its length and height. The upright stones on top of it are modern, to deter people from walking on it.
Sections of Hadrian's Wall still remain, particularly in its hilly central sector. Little remains in lowland regions, where it was used as a source of stone for new buildings.
Hadrian's Wall facing east towards Crag Lough. The rocky outcrop is the Whin Sill, of volcanic origin.
Bronze head of Hadrian, who commissioned the wall's construction, found in 1834 in the River Thames in London, around 280 miles (450 km) south of Hadrian's Wall
A fortification is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from Latin fortis ("strong") and facere.
Castillo San Felipe del Morro, Puerto Rico. The fortress and walled city of Old San Juan are a UNESCO World Heritage Site.
Castillo San Felipe de Barajas, Colombia. Cartagena's colonial walled city and fortress were designated a UNESCO World Heritage Site.
Maiden Castle in 1935. The Iron Age hillfort was first built in 600 BC.
Early 20th century aerial photograph of the fortifications of Valletta, Malta, which were built in the 16th and 17th centuries.