Chesters is one of a series of permanent forts built during the construction of Hadrian’s Wall. The cavalry fort, known to the Romans as Cilurnum, was built in about AD 124 above the west bank of the River North Tyne. It housed some 500 cavalrymen and was occupied for nearly 300 years until the Romans left Britain in the 5th century. Cilurnum is considered to be the best preserved Roman cavalry fort along Hadrian’s Wall. Pioneering excavations in the 19th century exposed the structures visible today. These excavations yielded one of the best collections of inscriptions and sculpture on Hadrian’s Wall.
At Chesters, the ditch that fronted the Wall was filled in and a recently built Wall turret demolished to make way for the fort. It marked the point where the Wall crossed the River North Tyne, the first major obstacle on its route from east to west. A large road bridge with stone piers whose abutments survive spanned the river there.
The first attested Cavalry unit at Chesters was the 500-strong ala Augusta ob virtutem appellata – ‘the cavalry regiment styled Augusta for its valour’. It is mentioned on an altar dedicated to Disciplina and dated to Hadrian’s reign (RIB 1496c). By around AD 180 until the end of the Roman period, Chesters Fort was garrisoned by a cavalry regiment originally raised in northern Spain, the ala II Asturum (‘the Second Asturians’).
The fort was of the usual rectangular shape, covering 2.3 hectares, with large, double gateway in each side. The walls were of stone, some 1.5m wide, backed by an earthen rampart and fronted by a single ditch on all sides. The defences were completed with four stone corner towers and eight interval towers, two on each face. In addition to the four monumental gateways, two smaller, single gates at either end of the via quintana gave access to the fort on the south side on the Wall.
Remains survive from various periods in the 300-year life of the fort but most of its interior is unexcavated and is still buried. The visible selection of buildings result from the excavation campaigns of Nathaniel Clayton, the wealthy land-owner of Chesters House and Estate, between 1843 and 1893. They include all six gateways, the two interval-towers in the southern defences, a small section of the fort wall to the immediate south of the northern interval tower, the headquarters building (principia), the commanding officer’s house (praetorium) with its own central heating system, as well as two barrack blocks that could each accommodate a turma or cavalry troop of about 30 men. The most impressive building remains are those of the headquarters building (principia) in the middle of the fort.
The site museum houses finds from the fort and elsewhere along the wall, including Roman sculptures, inscriptions and altars, many of them collected in the 19th century by John Clayton (see images here). Following his death in 1890, his nephew Nathaniel commissioned the building of a permanent museum (completed in 1896) in order to house the Clayton Collection.