The second largest gateway. It is primarily used for military purposes, and is frequently visited by numerous auxiliaries, legionaries, and their families. This gateway has the largest military sector of all gateways, and civilian access is prohibited in this area.

Various ships, as well as personnel working at military facilities on Mars and the Navalia orbital shipyards orbiting Mars, also frequently visit this gateway. While the Terra Gateway is the largest in terms of scale, the Mars Gateway presents the most magnificent spectacle in atmosphere, due to the docking of numerous massive legion spacecraft.