main entrance of ancient roman complex of palaces and temples felix romuliana by roman emperor galerius

ruins building monastery fortification estate castle chapel village tree rock abbey monument wall history main entrance ancient roman complex palaces temples felix romuliana emperor galerius serbia view inside building main entrance ancient roman complex palaces temples gamzigrad felix romuliana built 3rd 4th century emperor galerius heritage site travel architecture wall stone history brick monument close landscape nature location ruin fortification arch antique historical city zajecar eastern serbia europe