Martian tubes could be home for ‘cavenauts’ New Scientist

Our ancestors made their first homes in caves. Now it looks like the first humans on Mars will do the same.
An analysis of Martian geography suggests where to look for the right kind of caves. “At least two regions, the Tharsis rise and the Elysium rise, contain volcanic features which may be suitable locations for caves,” says lead author Kaj Williams of NASA’s Ames Research Center in Mountain View, California.
What’s more, the analysis suggests that caves in these regions will contain a ready supply of water, in the form of ice.
Lava tubes are the most likely form of cave that we could occupy on Mars. These tunnel-like caves were created when ancient lava flows solidified at the surface, while lava inside drained away.