Ancient Athens had its own "Great Wall" like China's, built to stop raids during the Peloponnesian War (431-404 BC).

The Citadel, Ancient City and Fortress Buildings ... blocks with ragged stone on lime mortar in its internal backfilling. The citadel is surrounded on three sides by steep slopes and has massive stone ...

Two ancient stone circles have emerged ... A mile north of Metheral lies the second stone circle, located near a feature called Irishman’s Wall. Although only six stones remain visible ...