The ruins of a tholos (circular memorial) in Archaea Olympia, Greece.
The Philippeion originally had 18 columns supporting its roof, sheltering 8 half-columns holding 5 statues of the Macedonian royal family. Built to honor and on behalf of Philip, it was not completed before his death, and was likely finished by his son (and designated heir) Alexander.
Olympus E-M1III, M.Zuiko 8-25mm f/4.0 lens
14mm, f/11, ISO 200, 1/500 sec.