If scores of cartoons and ancient cave drawings are to be trusted, caves were mankind's first shelter on Earth. How appropriate, then, that NASA thinks caves could play the same role on the moon.
NASA says that the moon has as many as 200 "lunar pits," which aren't exactly craters—they're probably not formed by asteroid or meteor impacts. More likely, they are formed when part of the moon collapses over a void or a cave. Most importantly, many of them probably widen underground, opening up to form large underground caves, where astronauts (or future moon dwellers) could probably live.
"Pits would be useful in a support role for human activity on the lunar surface," Robert Wagner, an Arizona State University researcher who discovered the holes, said in a statement. "A habitat placed in a pit—ideally several dozen meters back under an overhang—would provide a very safe location for astronauts: no radiation, no micrometeorites, possibly very little dust, and no wild day-night temperature swings."
So, that sounds pretty ideal, and would probably be a nice stepping stone before we have full-on lunar colonies on the moon's surface.
For the rest of the story: http://motherboard.vice.com/read/nasa-thinks-astronauts-could-live-in-caves-underneath-the-moon