Geology

One of the largest concentrations of rock paintings in Southern Africa.

This army of concretions is an unexplained geological phenomenon unlike anything else in the world.

Sweden's southernmost prehistoric rock art is hidden just outside Gothenburg.

When the river dries up, these stones start talking.

A steep and winding road in the Yorkshire Dales passes by these deep natural potholes.

This unusual rock formation looks like an apple that has been neatly sliced in half.

A cult archaeology conspiracy theory claims these West Virginia petroglyphs were written by Irish monks in Ogham.

Incredible miniature towns and buildings created and decorated with thousands of tiny rocks.

A striking, menacing sandstone peak towering above a landscape that's equal parts Mordor and the Moon.

Among the cliffs of the Elora Gorge is an oft-overlooked piece of celebratory graffiti.

A catapult rock from Gotland’s 13th-century civil war is still lodged in Scandinavia's best-preserved medieval city wall.

Faces carved into the cliffs create an otherworldly walking trail.

It reportedly took three years to sort through all the objects in this eclectic lifelong collection.

This fantastic cave remained unexplored until 1948 when three schoolboys discovered a hidden entrance.

The petrified remains of 150-million-year-old trees can be seen in and among the houses of the local villagers.

Crooked windswept pines give this old forest an enchanted and magical look.