During excavations at the site of today's Kamenitsa Square, parts of the foundations of the Propylaea – the main entrance of the Ancient Stadium of Philippopolis, were found. Probably, the Propylaea consisted of four or six masonry pillars supporting arches to the South and the North.
The main entrance of the Stadium is formed by pillars with marble pilasters. The latter are decorated with bas-reliefs featuring prize-vases with palm leaves, accompanied by Heracle’s attributes – lion skin, a club and a quiver. The original bas-reliefs are exposed in the Regional Archaeology Museum in Plovdiv. Because of these images it is believed that Hermes and Heracle have been the patron deities of some of the stadium games.
All the architectural marble elements of the Propylaea were tied to each other with lead-soldered steel cramps. In front of the entrance a granite pavement was uncovered, consisting of hexagonal blocks – 0.70 by 0.70m diagonally.