The Basin was a a landform located on Mar Sara, the remains of an impact crater that gouged a long bowl out of the planet's surface, located near the Stonewall Peaks. The remains of the crater rim had eroded over time and the crater itself was a rugged, barren landscape.
Despite the inhospitable landscape, the Basin saw terran settlement. Bunker Complex 3847 was located to the southwest and the Basin featured the settlement of Oasis Station, a switchback road linking the two settlements. However, the Basin was heavily irradiated by a nuclear strike in order to deal with the zerg present.