Stob Earth Pyramids

The Stob Earth Pyramids are rock formations, known as hoodoos, situated at the foothills of the Rila mountain range in south-western Bulgaria. They span an area of 0.7 km2 near the village of Stob, Kyustendil Province. The rock formations are up to 12 m high and up to 40 m thick at the base. Their shape is mostly conical to mushroomlike. Some of the columns are topped by flat stones.

Source: Wikipedia