Rhodes. Greece. The dry Moat that surrounds the walls of the medieval Old Town. Originally built as a formidable barrier to attack by the Knights, the moat is delightful place to wander with many giant old stone mortar balls littering the grounds. The old town is a UNESCO world heritage listed site and the best preserved, oldest and largest living medieval city in Europe. The 4km defensive walls were built by the Knights of St John during the 13th to 15th century to defend Western Europe against the expanding Ottoman Empire. Within the walls are a medieval warren of small alleyways and magnificent historical buildings. The island of Rhodes is the largest of the Dodecanese Island group and one of the most popular Greek Islands.