The petroglyphs of Fossum in the Swedish municipality of Tanum, Bohuslän date back to the Nordic Bronze Age (1800 - 1000 BCE). Together with other nearby petroglyphs from the Tanum Rock Engraving Area, they are included in the UNESCO World Heritage List of Archaeological Cultural Heritage.
The petroglyph field is located just off the N163, a few kilometres east of Tanum Church. This smooth rock panel shows various beautifully crafted motifs, such as hunting scenes, horn blowers, images of ships and animals (180 in all). A large number of men with axes, bows and swords characteristic of the Bronze Age are scattered across the rock panel. The ships are usually grouped together in a characteristic manner. The number of men on board the ships is marked with dashes.