to the Plain of Pylia. Below is Nestor's cave, where, according to mythology, the king of Pylos raised his oxen, and the bay of Voidokilia, whose beach is regularly ranked among the most beautiful in the world. It borders the Gialova lagoon (Osman-aga lake), located to the east and Navarino bay to the south. However, access to the Paleokastro may present some risks for the safety of visitors, due to its great deterioration. On the other side of the Navarino bay, the Neokastro, which is in a better state of conservation, looks out onto the island of Sphacteria, the bay of Navarino, and the city. It is one of the best preserved castles in Greece. It contains within its walls the well-preserved Church of the Transfiguration of the Savior, built by the Franks, later transformed into a mosque, then again into a Christian church. In the pine forest of the Neokastro is also the old barracks built by the French troops of the Morea expedition, which now houses the new archaeological museum of Pylos. Navarino aqueduct South of the city of Pylos, on the road to Methoni, is the old Navarino aqueduct, built in the 16th century by the Ottomans to meet the water supply needs of the Neokastro. Composed by two hydraulic systems, it led the waters from the water intakes of the plateau of Koumbeh (located near the town of Chandrinou about 15 kilometers northeast of Pylos on the road to Kalamata) and Paleo Nero (located near the village of Palaionero). The two systems combined into a single system that can still be seen today around Pylos in the district of Kamares. Then, thanks to an underground conduit of the aqueduct, the water penetrated inside the fortress to feed there the fountains of the Neokastro. Fallen into ruins until 1828, it was restored in 1832 by the French engineers of the Morea expedition, and was used to supply Pylos with water until 1907. Pylos city center Leaning against two hills, one of which is overlooked by the fortress of the Neokastro, the town of Pylos faces the bay of Navarino. Pylos preserves many houses from the 19th century. These are built of stone, with typical Messenian architecture and surrounded by spacious courtyards and gardens. They are built mainly between narrow streets, generally symmetrical, and according to the original urban plan established by French military engineers of the Morea