In Greek mythology, Acheron is one of the rivers which leads to the underworld.
Acheron is a planet connected via the Erebus bridge to its neighboring planet, Empyrean. Acheron was the first human settlement off Earth and is inhabited by humans who share ancestral ties to Earth. These inhabitants refer to themselves as Earthborn. The capitol of Acheron was Anicetus, with a Titan at its center. However, the city was destroyed during the Siege of Anicetus.