Out of this world

Out of this world: The bizarre 35,000-year-old rock towers that look like they belong on an alien planet

You’d be forgiven for thinking these striking images of jagged rock formations, twisting into the cobalt sky, were taken on an alien planet. 

In fact, the otherworldly towers can be found at the mouths of hot springs and on lake beds across the world and are known by geologists as tufa towers.

Despite their spindly, tough appearance, tufas are actually soft, porous stone made up of calcium carbonate that forms as lake water evaporates then algae, bacteria and mosses grow on top of the sediment. 

Fresh tufa pillows and nodules can contain trees, mould and leaves or volcanic cobbles.
The twisted limestone towers can grow up to 30ft and some of the oldest formations date back 35,000 years and appear in locations where lakes once existed, according to the United States Geological Survey. 

Holidaymakers keen to see the surreal landscapes on Earth can find them in locations including Greenland, Italy, California and Nevada.