A small 12th c. Byzantine chapel of the vaulted single-aisle basilica type.
The chapel is built at the site of the north tower of the Diateichisma gate, called Dipylon above the Gates, and near a small temple-shaped structure, built in accordance with the ancient tradition of some divinity protecting the gates.
The construction of the capel is probably associated with the final phase of the Diateihisma fortification wall (12th c. A.D.). Inside the church, frescos are preserved that date to 1732 according to the building inscription. The surname “Loumbardiaris” (the Cannonneer) is connected with the tradition that the church was chaved by a miracle around 1640-1650, when the Turkisk commander of the Acropolis, Yusuf, bombed the church fron th Propylaea. The following day lighting struck the Propylaea, killing Yusuf and his entire family.
The church was undergone many changes over time. Its current form is owing to the restoration of its Post-Byzantine phase by the architect D. Pikionis in the 1960s.