Hisar Kapia is a medieval gate in Plovdiv's old town and one of the most famous tourist sights in the city. The gate was built in the 11th century AD over the foundations of a gate from Roman times (probably from the 2nd century AD). Hisar Kapia is one of the three entrances (Eastern, Northern and Southern) to the acropolis of ancient Plovdiv. During the rule of the Ottoman empire revival houses were embedded in the remains of the old stone walls around the gate.