The Mariner Valley is a canyon that runs along the equator of Mars. It was one of the first large-scale settlements on the planets.
It contains five neighborhoods burrowed into the sides of the vast canyons, linked together by Haizhe, a network of bridges and tubes that make a figure resembling a cartoon jellyfish. Later, a high-speed line to Londres Nova was added.
It was originally settled by Chinese, East Indians and Texans from Earth, and people from the Mariner Valley may look like any of those ethnic group, but they generally speak with a Texan accent; for example, Alex Kamal is from there, has the skin complexion and hair color of an East Indian, but speaks with an exaggerated Texan drawl.