Roman Fortresses

fort (fortlet/fortress) [MC]. A military construction that combines accommodation for troops, their transport, and their equipment with a defensible stronghold. In general, the design of a fort will reflect the style of warfare anticipated, and the kind of defence that might be mounted. Amongst the most widespread set of forts known through archaeological investigation are those built by the Roman army. Indeed, these provided models for later armies to copy and adapt. Roman forts were either temporary (also called marching camps), built of earth and wood with tents rather than buildings, or permanent/long-term, in which case they were built in stone and wood with considerable investment in the fortifications, infrastructure, and accommodation. Those used by cavalry units would have an annexe for stabling the horses if there was insufficient room within the main fort. The basic layout of Roman forts followed set patterns and all were built to the so-called ‘playing-card’ shape. Three main sizes can be recognized: fortlets of less than 1ha; forts of between 1ha and 4ha to accommodate between 500 and 1000 troops; and fortresses which generally cover between 17ha and 20ha and were designed to accommodate a whole legion. The Roman term for a fort is castellum.

The Concise Oxford Dictionary of Archaeology. Timothy Darvill. Oxford University Press, 2002.