Gamla Stan, the medieval center of Stockholm, Sweden. It consists of Stads Island, Helgeands Island, and Riddar Island. Most of the buildings in this area date from the 16th and 17th centuries and are legally protected from renovation. Stads Island contains the Royal Palace; Storkyrkan, also called the Cathedral, or Church, of St. Nicolas; the German Church; the House of Lords; the government offices; the Stock Exchange; and a number of other notable buildings. Riddar Island is dominated by the Riddarholm Church. The House of Parliament and the National Bank are on Helgeands Island.