English: Promethei Planum, an area seasonally covered with layer of ice a more than 3500 m thick in the martian south polar region, was the subject of the High Resolution Stereo Camera’s (HRSC) focus on 22 September 2005 as Mars Express was in orbit above the Red Planet.

Promethei Planum lies at approximately 76° south and 105° east. An approximately 100 km-large and 800 m-deep impact crater is visible in the northern part of the image (1). The crater’s interior is partly covered in ice. In the centre of the image are structures that may have been created by basaltic lava flow from a volcano (2). This area is covered in ice. The dark dunes towards the bottom of the image are most likely made up of dust originating from this lava flow or volcanic ash (3).

A broad sheet of ice, which is an extension of the south polar ice cap, is located south of the lava flow, to the left in the (nadir) image. The steep flanks clearly show white, clean ice (4). The thickness of the ice is between 900 and 1100 m.