Rotunda of Galerius, Thessaloniki

The oldest monument in Thessaloniki, the Rotunda (also known as Agios Georgios) is a massive round building that was first a Roman mausoleum, then a Christian church, then a mosque. Its interior is decorated with Early Christian mosaics; outside is the city's only surviving minaret.


History of Rotunda of Galerius

The Rotunda was built by the Roman emperor Galerius (305-11) as part of a large palace complex in Thessaloniki. It was probably intended to be his mausoleum, but it was never used as such.

Many Christian legends about the persecuting emperor's last years developed in Thessaloniki, such as his repentance on his deathbed as he suffered from painful and disgusting sores (an affliction ascribed to many enemies of the Church in early writings). It was also said that his daughter was secretly a Christian, who was martyred as well.

The Rotunda of Galerius was converted into a Christian church in the late 4th century or mid-5th century. The date of conversion to a church has been difficult to determine with any certainty. There is no written documentation about the event, so dating has to be based on analysis of the style of the mosaics and the historical situation of Thessaloniki in these early centuries.

With regard to the latter, Thessaloniki was always an important city and it was given a further boost after Constantine developed its harbor. The city became even more important after the mid-5th century, when it became a provincial capital and the base of the main military general of the west. Thessaloniki flourished, and developed at a fast pace into the mid-6th century.

Many grand churches were built in this period (including Panagia Acheiropoietos, St. Demetrios and Hosios David), and so it seems a logical period for the Rotunda transformation and decoration as well. However, the classical style and Early Christian themes of the mosaics have led other scholars to date it to the late 4th century, perhaps under the patronage of Emperor Theodosius I (379-95). The latter is adopted by most guidebooks.

The Ottoman Turks ruled Thessaloniki from 1430, and in 1591, Agios Georgios was converted into a mosque. On the Islamic calendar it was the year 999, when the end of the world was expected by some. Fortunately, the mosaics that survived until then were not harmed further by this conversion; they were simply painted over.

After serving three religions, the Rotunda is now a deconsecrated museum. It has been undergoing extensive restorations ever since the destructive earthquake of 1978. The Rotunda reopened in 1999, but at the time of writing (late 2009) the ancient mosaics around the dome are still covered in scaffolding.

What to See at Rotunda of Galerius

The Rotunda is an austere structure built entirely of brick on a circle-within-a-circle plan with 20-foot-thick walls. To transform it into a church, Thessaloniki's Christians converted the southeast niche into an arch, added a sanctuary, moved the main entrance from the southwest to the northwest side, added a narthex, and built another ambulatory around the outside (which has not survived). The slender, freestanding Turkish minaret is the only one to survive in Thessaloniki.

The interior was covered in glittering Byzantine mosaics, of which only a few fragments survive. Most of the damage was done by earthquakes over the centuries. They mosaics are Hellenistic in style and are some of the finest examples of mosaic work to survive from this period. The quality of the work and complexity of the job suggests to some scholars that the workers were from Constantinople, probably sent by the emperor.

From the fragments and other sources it has been possible to reconstruct most of the original mosaic program, the overall theme of which seems to suggest the Second Coming of Christ.

The dome mosaic is now lost entirely, but its subject is known from the fortunate survival of its underdrawing. It depicted Christ, dressed in imperial purple and seated or standing on a shield. He held a cross in his left hand and raised his right hand upwards. This is a notable example of the influence of imperial elements in Early Christian art - the Roman army would often proclaim an emperor by elevating him on a shield.

This central scene was surrounded by 24 stars and a garland border (which survives intact) and supported by four Victories or angels, whose heads and wing tips survive. Between the angels were a phoenix and a luminous cross. Lower on the dome was a set of 24 to 36 standing figures, perhaps apostles and angels, of which only some sandaled feet remain.

The drum of the dome bears fragments of eight scenes, each in an architectural framework full of symbolic decoration (crosses, lamps, books, doves, peacocks, etc.) and centering on two or three martyred saints in prayer. Each saint wears slightly different vestments and has individualized features and a lively expression.

Inscriptions provide the name, occupation and festival month of each saint. They are all eastern saints and many were martyred under Diocletian (r.284-305). They are as follows:

The choice and grouping of these saints is intriguing. There is no other known example in Byzantine art of this grouping of saints or even its compositional arrangement. Many of the festivals contradict known church calendars, both Greek and Latin, and some of the names (e.g. Basiliskos and Therinos) are not known anywhere else. There is no record in Byzantine writings of a soldier named Leo who was martyred in June.

Golden mosaics with medallions of birds and fruit (restored 1885) decorate the southeast recess, and the apse vault bears a faded frescoof the Ascension from the late 9th century.

In the yard around the Rotunda are marble fragments from the Byzantine church (including an ambo and various other carved marble slabs), Jewish tombstones, and other artifacts.

Quick Facts on Rotunda of Galerius

Site Information
Names:Agios Giorgos · Ayios Giorgios · Rotunda · Rotunda of Galerius
Categories:churches; mosques; temples; change of religion; round buildings; rotundas
Dedication: St. George
Status: museum
Visitor and Contact Information
Coordinates:40.633289° N, 22.953068° E
Address:Ayios Yioryos Sq.
Thessaloniki, Greece
Hours:Daily 8:30am-3pm
Lodging:View hotels near Rotunda of Galerius
Note: This information was accurate when first published and we do our best to keep it updated, but details such as opening hours and prices can change without notice. To avoid disappointment, please check with the site directly before making a special trip.


  1. Sherry Marker and James Pettifer, Blue Guide Greece: The Mainland, 7th ed. (W.W. Norton, 2006), 600-02. Dates the mosaics to "before 400."
  2. Robin Cormack, Byzantine Art (Oxford History of Art) (Oxford University Press, 2000), 25-31. Following a detailed stylistic and historical analysis, this source dates the Rotunda's conversion into a church to the late 5th or early 6th century.
  3. Rotunda (aka Ayios Yioryos) - Frommer's Greece. Source for visitor information only.

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