OB 15cm Geschütz is a German World War II coastal artillery bunker located in Norway. Built during the German occupation, it formed part of the Atlantic Wall defensive system designed to protect against Allied naval incursions. The designation 'OB' refers to 'Offener Bau' (open construction), indicating a reinforced concrete structure housing a 15cm gun battery.
These bunkers were strategically positioned along Norway's extensive coastline to control sea lanes and defend key ports and fjords from potential Allied attacks.