Het Steen, the oldest preserved building of the city of Antwerp, was built between 1200 and 1225 after the Viking incursions in the early Middle Ages. It was originally called the Castle of Antwerp. Inside the castle were key institutions such as the "Vierschaar" (former courthouse), the "St. Walburga Church", "Het Reuzenhuis" (Giants House), "Het Steen" (The Rock), "The Yard" and the "Fish Market".Unfortunately, the building, preserved to this day, is only a small part of the old fortress. The old fortress covered an area several times larger. The entire complex was surrounded by a massive defensive wall. At that time the fortress made it possible to control the access to the Scheldt River and to guard the entrance to the city from the direction of the Western Scheldt.