The track was the part of the Stadium, where sports and other competitions took place. At the edges of the track there were draining canals with brick shafts which led the water towards the canal under the ancient vaulted passage-street. 

The track of the ancient stadium was approximately 250 metres long and 32 metres wide. Its length was 600 Roman feet equaling the Roman measure for one stade. Since its width is comparatively small, the track most probably was not used for chariot races. The track was three-layered, the finishing one being mortar.

The track surface in front of the seats - west side seats / K. Varbanov