Isegran is the first place in Fredrikstad mentioned in history. The Earl of Borgarsyssel, Alv Erlingsson, also called MindreAlv, had a small fortress on Isegran in the late 1200s. In the 1670s, the island was fortified with a large battery platform, Isegran tower, and later a small fort was built to protect the river. Until 1685 Isegran was the royal shipyard for the danish-norwegian fleet and during the Great Northern War, the island was the naval base for Peter Wessel Tordenskiold. The historic island can be reached via the Kråkerøy bridge or with the city ferry.
References:The first written record of church in Danmark locality date back to the year 1291. Close to the church are several stones with a Christian text and cross inscribed. The oldest parts of the present red-brick church are from the 1300s. In the late 1400s the church was enlarged to the appearance it has today. The church has been modified both internally and externally several times, among other things after the fires in 1699 and 1889. There are lot of well-preserved mural paintings in the walls.