A balancing rock seems to be an oddity of nature. It often appears as a large boulder perched on a stone pedestal. Geologists call them precariously balanced rocks or PBRs for short. Typically, the two sections are all one piece but the lower half has eroded faster. This balancing rock (lower right) is visible from the Badlands Loop Road. The toadstool-shaped hoodoo was formed about 30 million years ago.