This is a semi ruined castle which was built on top of the mountain of Agios Stefanos at a height of 295 m. Although it is not in good condition, the castle is one of the best preserved castles of Tilos. In the same place there used to be a Hellenistic acropolis, remains of which are visible till nowadays. The castle covers an area of 6,750 m2 and the perimeter of the walls is 390 m. The gate dates back to the Hellenistic period, but was modified by the Knights in order to reduce the height of the opening.

Since 1994 the Paleontological Museum of the island is housed in a small residence on the main street of Megalo Chorio, near the Town Hall. It includes fossilized bones of dwarf mammoths and other findings from the excavations at Charkadio Cave of Messaria.

This is a ghost village located next to the main road that connects Megalo Chorio with Livadia. Before the war, Mikro Chorio was not that small and had over 750 permanent residents. However, the population started decreasing when people started moving to Rhodes, Athens, Australia and America. Those who stayed behind moved to Livadia. From the 220 houses of the settlement only the walls are preserved nowadays. At the top of the hill you will find the remains of a medieval tower which also offers a beautiful, panoramic view of the settlement.