The Atacama Desert in Chile is one of the most hostile places on Earth - you could even say that it is one of the least Earth-like places! This is not due to any sort of extreme heat (temperatures typically top out in the upper 90s there), but rather is caused by an unprecedented lack of precipitation in the area. Located between the Andes Mountains and the Pacific Ocean, the Atacama's exceptional dryness is generated by the combination of a high-pressure system pushing storms out to sea and the eastern Andes cutting off moisture from the Amazon region.
The desert is so dry that its conditions in many areas are comparable to the surface of the planet Mars! These areas are so dry that NOTHING can survive, not even microorganisms such as bacteria! The Atacama is one of the only deserts on Earth in which this is the case - in most under deserts, microbes are able to survive on moisture located inside or beneath translucent rocks. This means that anything unlucky enough to wander into the Atacama Desert will not rot after it dies!
NASA even did a side-by-side comparison of Mars and the Atacama Desert. Check it out.
Also, while the lack of water keeps most life forms from living in the Atacama Desert, there are actually over a million people living there! This includes miners harvesting the area's natural resources, astronomers making use of coastal observatories, and fishing villages on the coast. Pretty weird. Read more.