 Evidence exists to show that Swindon's quarries were in use at this time to produce stone for villas and clay from the Whitehill region (now West Swindon) was used to produce "Whitehill Ware" pottery.Burial grounds dating to the 4th century have been found in Purton, but the most substantial find was made in 1996, when contractors developing an area of Groundwell Ridge uncovered the buried walls of Roman buildings.Described as "a site of great importance, with a large complex of buildings, a hypocaust (a system of under-floor heating, usually found as part of Roman bath houses), walls covered with painted plaster and a carefully designed and constructed water supply.