Gotland is one of the richest historical regions in Sweden, with around 100 medieval churches and myriad number of prehistoric sites, including stone ship settings, funeral mounds and the remains of hilltop fortresses. The isle lies virtually halfway between Sweden and Latvia, in the middle of the Baltic Sea, approximately equidistant from the mainland ports of Nynäshamn and Oskarshamn. Gotland is both a region and a county. Visby is the only township, but there are numerous large, and many small villages. The large isle, Fårö, lies off Gotland's northeastern tip and the isle national park of Gotska Sandön lies 38km further north. Stora Karlsö and Lilla Karlsö are two small islets just off the western coast.