In 1814, the fortress was attacked and encircled by Swedish forces. Among other things, they had landed at Tangen at the southern tip of Kråkerøy and advanced to a position later named Svenskeberget (literally, 'Swedish hill') southwest of the fortress. From there, the Swedish forces had good positions and the advantage of the height of the terrain, which allowed them to fire their cannons directly into the fortified town. After a brief bombardment, Hals surrendered the fortress on August 4, 1814.