17th century arch architecture Argolis castle defence defense elements fort fortress Greece historical landmark Morea nafplio old Palamidi Peloponnese power ramparts stairs steps stone stronghold venetian walls access entrance block building center centre city concrete concrete jungle hostel hotel motel path paved pavement rest sport street town train training training centre treeless urban windows battlements angles appearance architectural-elements bell-tower bells blue circular distinctive glass height high metal modern round rounded street-scene tall tourism tourists tower