Interior

The focus of the interior is on the central nucleus and the harmony between its square base and round dome. The main apse is surrounded by four two-storey sacristies. The church is approached through a narthex, built in AD 1181 in a cross-in-square plan with the roof supported by four columns (the earliest known example of this plan). The ornamentation of the capitals of the columns with symbolic sculptures in the shape of animal heads adds distinctive expression to this narthex.