ancient architecture castle decay defence defense desuetude fort fortress Greece Greek high hilltop historical Mystras old ruins stone stronghold UNESCO World Heritage view wall window elements Golan Heights hills Israel Mivtzar Nimrod mountains Nimrod Nimrud Qal'at Namrud Remains trees valley arch blocks stairs steps archaeological site beach blue clouds coast entrance Gower Great Britain hill landscape Pennard Pill sea shore sky Three Cliffs Bay tower wales water welsh homes houses village inscription letters writing capstone room strong lookout sentry