Type: Temple Or Shrine
A perfectly circular building with a single entrance facing due east, its walls were of finely-dressed masonry blocks 4 ft. thick, an outer diameter of 28 ft., an inner diameter of 20 ft. The corbelled roof still survived to a height of 22 ft. when the building was demolished in 1743, but may originally have stood about 24-25 ft. high with a central hole in the roof possibly 6-7 ft. in diameter.
This building had no known parallel anywhere in the Roman empire. Prior to its destruction it was visited by antiquarians who have left vague records of inscriptions and carvings of eagles and Victories. A single large stone slab lay in the centre of the floor forming a pedestal for a statue, one bronze finger of which survived, lodged in a crevice. It is possible that the circular Roman building here was a temple dedicated to the goddess Victory, called a tropaeum by devout classicists.