Crisium City
From Halopedia, the Halo wiki
Crisium City was a city located on Naniwa, Luna. It is notable for being the birthplace of The Rookie and Mickey.[1]
Trivia
-Crisium or more accurately Mare Crisium is a real location on the moon located on the near side facing earth. It's a large "sea" much like the famous landing site of Apollo 11 mission, very flat and over 500 kilometers wide it would be an good location for a lunar colony. It's location can be seen in this image
