The remarkable preservation of this Bulgarian site and the comprehensive nature of the British research programme combine to provide a unique insight into the physical, economic and palaeo- environmental history of a Roman city from the early 2nd to the late 6th century A.D. This first volume contains the results of the excavations, geophysical surveys, coins, epigraphic finds and an analysis of the Severan frescoes. It also summarises the results of the large environmental programme, small- find, architectural material and ceramic studies and assesses their implications for the city in its regional context and its relations with other parts of the Roman Empire and the early Byzantine world.