Chryse Planitia (Greek, "Golden Plain") is a smooth circular plain in the northern equatorial region of Mars close to the Tharsis region to the west, centered at (28.4°N 319.7°E). Chryse Planitia lies partially in the Lunae Palus quadrangle, partially in the Oxia Palus quadrangle, partially in the Mare Acidalium quadrangle. It is 1600 km or 994 mi in diameter and with a floor 2.5 km below the average planetary surface altitude, and is thought to be an ancient impact basin; it has several features in common with lunar maria, such as wrinkle ridges.