Perspective view of Sirenum Fossae in the Southern Highlands of Mars. The image shows the region centred at about 28°S, 185°E. It extends about 230 by 127 kilometres and covers 29,450 sq km, roughly the size of Belgium. The largest impact crater here is around 50 kilometres in diameter, and indicates that this region is ancient because such large craters rarely form in more recent times.
Credit: ESA/DLR/FU Berlin (G. Neukum).