Eurajoki (Swedish: Euraåminne) is a municipality of Finland located in the region of Satakunta in the province of Western Finland. The municipality has a population of 5,938 (30 June 2015) and covers an area of 643.78 square kilometres (248.56 sq mi) of which 298.39 km2 (115.21 sq mi) is water. The population density is 17.19 inhabitants per square kilometre (44.5/sq mi).Two of Finland's four nuclear reactors are on the island of Olkiluoto in Eurajoki, and a third one is under construction.