The Christian cemeteries, often organised around a 'martyrion' (martyr's tomb), lie outside the city walls, usually in the areas originally occupied by pagan cemeteries. The most important, in terms of density, variety of grave types and their decoration, are the cemeteries of Thessalonike.
The commonest types of graves were built cist graves and vaulted-roof cists. These had a built headrest and their interior was plastered or covered with marble slabs, while the east section of the vault was open and there were projecting stones or steps on the inside, down which the dead was carried.
The wealthier classes had monumental tombs, such as domed mausoleia of 'cubiculum' type (Thessalonike, Naissus).