 Nynäs Castle is located about 80 km south of Stockholm, between the historic towns of Trosa and Nyköping.Its nature reserve is the largest in the province of Södermanland, spreading out for 8070 acres of land.The manor-house was built by the Gyllenstierna family in the late 17 century and is today considered to be one of the best-preserved historic houses open to the public in Sweden.