 In 1904 the name Älvsborg Fortress was given to the new coastal fortress at the mouth of the Göta River, whose strongest fortification, Oscar II's Fort, started construction in 1899 on Västerberget.The fortress, whose task, like previous fortresses, was to secure both Gothenburg and the Port of Gothenburg and the Swedish Navy's rallying point there against attacks from the sea, was in 1907 equipped with new modern artillery guns.The main body of the fortress consisted of two 24 cm guns model of 1904 mounted on disappearing carriages and some 15 cm gun turrets and other light guns.