In the 13th century, the town of Riquewihr became the property of Burkhardt, lord of Horbourg. He had walls built and surrounded Riquewihr with a wide and deep moat in 1291. It became a secured location 984 ft long (300 m) and 721 ft wide (220 m). At the same time, it acquired the status of a fortified city. Two doors, equipped with a drawbridge and a portcullis, guarded its entrance. The Dolder gate is surmounted by an 82 ft (25 m) tower on four floors. From the top of the bell tower, the guard, who lived there, could give the alarm in the event of enemy attacks.