The Arch of Galerius or Kamara and the Rotunda are neighbouring early 4th-century AD monuments in the city of Thessaloniki, in the region of Central Macedonia in northern Greece.
Wikipedia https://en.wikipedia.org/wiki/Arch_of_Galerius_and_Rotunda
Address 43 Δημητρίου Γούναρη, Θεσσαλονίκη 54635, Greece
Coordinates 40°37'55.918" N 22°57'6.482" E