The Discovery of Petroglyphs

The first written references to prehistoric rock art were by the Chinese philosopher Han Fei in the third century BC. Europe had to wait some 1,700 years. There, what people saw scared them.

In 1458 Pope Callixtus III condemned cultic rituals in a cave decorated with horse figures. In 1460 Pierre de Montfort, a traveller through the Alps, complained to his wife of a ‘hellish’ valley ‘with figures of devils and a thousand demons carved everywhere’.

But the first person to detail what they saw was a university lecturer from Oslo, Peder Alfsön. He was responding to a nationwide call from the Danish antiquarian Ole Worm for information about ancient monuments and the beliefs surrounding them.

The site Alfsön found was at Backa Brastad in Bohuslän, Sweden. There are hundreds of panels there. He reproduced just one, depicting animals, humans, and ships, but somehow missed a key feature of the panel’s 1.5-metre warrior figure – its enormous penis.

Alfsön, who died on 3 May 1663, believed the carvings to be the work of medieval stone masons, which is perhaps why Worm ignored them in his six-volume Danicorum monumentorum. They were correctly dated to the Bronze Age by Oscar Montelius in the late 19th century.