Greece 2023: Thessaloniki II - Arch of Galerius, Tomb of Galerius, Heptapyrgion

During the period of the Roman Tetrarchy (285-324 A.D.) in which the Roman Empire was divided in rule between two Emperors and two caesars (emperors in reserve might not be a bad concept), Thessaloniki served as a capital for the province of Illyricum.  Galerius, one of the Tetrachs, eventually became Emperor (305 - 311 A.D.) but had previously served as caesar (293 - 304 A.D.).  At one point stationed in Thessaloniki, he had an Arch raised to commemorate his victory over the Persians in the battle of Salata in 298 A.D. Originally built as part of the palace complex of Galerius in the last 290's A.D. only a few pillars and the masonry portions of the Arch survive.

The Rotunda of Galerius (or The Rotunda of St. George) dates from the same period and is directly north of the arch.  Originally likely built as a mausoleum (similar to the tomb of Hadrian), it appears to never have been used for that purpose. It has instead been both a church and a mosque; the minaret seen in the picture is the last remaining minaret in Thessaloniki.  It dates as one of the earliest existing Christian church buildings.

As an item of interest, the brick walls are approximately 18 ft/6m thick.

The Heptapyrgion is a Byzantine/Ottoman Fortress (and then prison) built on the top of the acropolis of Thessaloniki with a commanding view of the town and the harbor.  From the top, one can follow the circuit of the walls down to the harbor (and The White Tower).  It was used as a prison up to 1989.

A plaque in the gate of the Heptapyrgion. Placed there in the 14th or 15th Century A.D. (if I recall correctly), it commemorates the repair of the gates by the mother of the local ruler.

An example of the city remaining city walls.  They just exist throughout the city.