The site of Calstock Roman Fort probably dating from the 1st century AD. This is only the third Roman fort to have been found in Cornwall and the first with possible associations with Roman military interests in Cornwall’s mineral resources. The site is located on a spur above the river Tamar near to St. Andrew’s church in the parish of Calstock, Cornwall.

A geophysical survey in 2007 revealed the outline of a Roman fort enclosed by two ramparts and two ditches. The fort is c170 x 160m with double ramparts. Its internal area is approximately 140m by 130m (0.42ha) which is much larger than both the other Cornish Roman forts of Nanstallon and Restore.

This is much larger than the other two known Roman forts in Cornwall; Nanstallon Fort and Restormel Roman FortletRestormel Roman Fortlet[/link_post. Two ramparts and ditches were uncovered. The outer rampart is approximately five metres wide and is constructed of clay and shillet from the digging of the ditches. The sides of the rampart were held together with timbers on both faces. Two ditches were uncovered between the inner and outer rampart with characteristic v-shaped profiles and square-cut bases which is typical of Roman military sites. They were 2.8m deep and approximately 3.5m wide. The outer rampart was also approximately five metres wide and the investigations show that it was capped with large sandstone rubble on the western and southern sides of the fort. The excavation revealed an inner rampart which was approximately 5m wide and constructed of clay and shillet cast from the digging of the first ditch. It was revetted with timbers on both faces. The outermost revetment was constructed of worked timbers 30cm square. These have been interpreted as forming part of a timber super-structure or palisade.

Just outside this rampart a stone-lined furnace structure was excavated. Finds from it included Roman pottery, fragments of furnace lining and some ore and slag which suggest that Roman metalworking was taking place in the 1st century AD. A track leading into the fort was also identified.

Like the other two sites it was found close to mineral deposits associated with tin mining which may be an important factor in the Roman occupation of Cornwall.

Sites near Calstock Roman Fort