rotunda mausoleum of galerius in the city center of thessaloniki, greece, landmark and historic monument built in 4th century, now

rotunda galerius thessaloniki greece mausoleum historic landmark monument city center architecture 4th century byzantine building exterior greek roman church agios georgios orthodox minaret history stone old ancient tourism travel destination attraction sightseeing famous antique archeology heritage town age hellenic macedonia copy space sunny blue sky nobody built now museum