The magnificent natural harbor of Navarino Bay is 5.5km/3.4 miles long from north to south and 3km/1.86miles wide with a depth of 22-55meters/66-180.4 feet. The island of Sphakteria (described above), encloses it on the west. The only reasonable entrance is on the south and is 1190meters/3903feet wide and divided into unequal channels by the islet of Plylos and the Tsichli Baba Rocks. The islet has a lighthouse on it and the French Monument, built in 1890 when the bodies of Frenchmen killed in the Battle of Navarino were transferred here from the cemetery on the mainland,along with the dead from the Morea Expedition of 1828-30. On a low rock in the harbor's center is the Memorial to the British Sailors.
The island of Sfakteria, which is uninhabited, and which all but closes the Bay on the west, is 4.5km /2.79miles long and 450-900 meters/1476-2952feet wide, with an interior covered with thickets and steep cliffs on the harbor side. The highest point, at Aghios Ilias (168meters) is partly enclosed remains of a huge ancient stone wall, where the Spartans made their stand.
There are some tombs and monuments on the island and the wrecks of the sunken Turkish ships can be seen below the waters near the north end, where a chapel sits near the 'Monument to the Russians Sailors'.
The ancient acropolis and castle (Palaiokastro), about a ten km trip from the modern town, sits up on a ridge across the shallow straits from the northeast end of the island, with a path leading up to it. Also known as 'Old Pylos', this is likely the setting of the prehistoric Palace of Nestor.