The more intact and accessible of two castles that lie on either side of Navarino Bay, Neo Kastro was built by the Turks in 1573 on the hilltop at the southern edge of town. It affords excellent views. Within its formidable walls is a mosque converted into a church, plus the hexagonal acropolis, used as a prison until the 1900s. The complex now houses Pylos' impressive archaeological museum and interesting displays on underwater archaeology.
In the museum, a selection of modern exhibits relate interesting finds from around the Pylos area, testifying to human presence from the Palaeolithic period to Roman times, and the Mycenaean past in the hinterland and at Voidokoilia. Highlights include the late-Roman bronze Diaskouri sculptures of two men, fine Mycenaean-era ceramics and jewellery, a stunning glass bowl, a Linear B tablet and fragments of wall paintings.
The underwater archaeology exhibition stretches across two buildings and the alcoves of the acropolis, covering finds from various shipwrecks around the Peloponnese as well as submerged settlements. The role of the amphora is given detailed treatment. A good video gives an introduction to this crucial field.