The Cathedral of Agia Sophia is one of the most important Byzantine monuments of Thessaloniki. A sample of a transitional cruciform with a dome and a peristole was built in the 7th century, on the site of a previous temple that had been destroyed by an earthquake. It is characterized by its majestic architectural structure, dominating the area of the square that bears its name, while inside it there are special murals and ornate mosaics, created in different periods.
During the Fourth Crusade, it was converted into a catholic cathedral for twenty years (1204-1224), returning to Orthodox Christian worship with the Byzantine re-rule of the city for the next three centuries. In 1524 it was converted into a mosque by the Ottoman administration of the city, operating until the liberation, in 1912, when it was re-assigned to the Greek church.
Agia Sophia ("Temple of the Wisdom of Agia Sophia") is on the UNESCO World Heritage List, operating in the city center and being a very important attraction due to its religious, historical, and architectural peculiarity.