town, south of Oslo, southeastern Norway. Located on the eastern shore of Oslo Fjord at the mouth of the Glomma (Glåma) River, it was founded in 1567 by Frederick II as a fortress town and has remains of the original fortifications. Fredrikstad's excellent harbour, protected by the island of Kråkerøy, is open year-round. Sawmilling, shipping, and fishing are the main industries; lumber, chemicals, granite, and feldspar are exported. Fredrikstad is known for its workshops that create models for the distinctive Norwegian products, notably glass, silverware, and textiles. The surrounding area is rich in rock carvings, monumental stones, and graves dating back to the late Stone Age. Pop. (2007 est.) mun., 71,297.