LillehammerHamarNesGjøvikHelgøya Helgøya is an island in Mjøsa located in the Ringsaker municipality of Innlandet county, Norway. It was formerly a part of the Nes municipality. With an area of 18.3 km², Helgøya is the largest fresh-water island in Norway. The island is located south of the Nes peninsula, and has been connected to the mainland by the since 1957. Helgøya Church (Helgøya kirke) was inaugurated on 7 December 1870. The chapel was built in timber and blockwork in the Gothic Revival style. The church has about 200 seats. The chapel was restored and partially rebuilt in the 1970s.