Agia Sofia is one of the oldest churches in the city operating till today. It was built in the late 7^th-early 8^th century in the place of an early Christian Basilica of the 5^th century. It had been the metropolis of Thessaloniki for about 5 centuries (from 1000 to 1500 AD) as well as a mosque for a long time, like almost all Orthodox churches during the Ottoman Empire. It is a massive square building, which does not predispose you at all for what you will see in its interior. As far as its architecture is concerned, it is a combination of a three-aisled Basilica and a four-columned cross-in-square church, i.e. it has two colonnades that separate the central from the adjacent aisles and four columns supporting the dome. Agia Sofia is famous for its tessellations: an imaginary cross on a blue background surrounded by stars, the Ascension of Christ on the dome and the Panagia Platitera on the niche, works of the 8^th, 9^th and 12^th century respectively. All the murals that have been preserved are works of the 11^th century. The magnificence of the church "is ironed out" by the cute vegetal and ornamental motifs that will draw your attention, works of the early 20^th century. Perfectly harmonized with the imposing atmosphere of the church is the chanting of the Byzantine Choir of Ch. Taliadoros. This is a magnificent church from all points of view calling to mind Agia Sofia of Constantinople. Moreover, this is another UNESCO World Heritage Site in the co-capital.