Desolation City was a domed city on Mars during the 19th Century. Edward Turnbull and Amelia Fitzgibbon found their way to the city shortly after their accidental arrival at Mars, and lived there for a brief while. They were able to pass for Humanoid Martians and were not stopped during their time living there.
The city, like others on Mars, has an electromagnetic shield to prevent the escape of the atmosphere. This was designed by the Nonhumanoid Martians to delay death by the slow, natural depletion of Mars' atmosphere. ("The Space Machine")