Rotunda, Archaeological monument and church in Thessaloniki, Greece

The Rotunda is a cylindrical monument with a large dome and eight arched recesses in Thessaloniki, Greece. The walls reach a thickness of more than six meters and support the weight of the dome that spans the interior space.

Built around 304 under Galerius, probably as his mausoleum, the Rotunda stayed unused after his death in 311. At the end of the 4th century, under Theodosius I, it became a Christian church, perhaps the one Byzantine sources call the Church of the Asomatoi Powers. In 1590 Sheikh Suleiman Hortaci turned it into a mosque and added the minaret; in 1912 it was rededicated to Saint George.

The building takes its name from the circular layout that shapes every part of the interior space. Golden mosaics with saints and angels line the walls, reminding visitors of the community that first worshipped here fifteen centuries ago.

The monument opens from Tuesday to Sunday in the morning and closes in the afternoon, with Monday serving as the weekly rest day. Visitors should wear sturdy shoes, as the floor can be uneven in places and the steps may show wear.

The minaret added in 1590 is the only one still standing in Thessaloniki. The marble base of a monolithic ambo found outside the south propylaeum is now kept in the Istanbul Archaeological Museums. The dome mosaics, the oldest wall mosaics of the Christian East, show fifteen martyrs in wide robes before peacocks.