This vertical view shows the mouth of Kasei Vallis, one of the largest outflow channels on Mars.

The image was taken by the High Resolution Stereo Camera (HRSC) onboard Mars Express in orbit 61 from an altitude of 272 km. The resolution is 12 m per pixel.
The image centre is located at 29.8° north and 309° east, the image width is 130 km, North is up.

The part of the outflow channel seen in this image has most probably been carved by glaciers or gigantic water-related outflows from terrestrial subglacial lakes. The blackish-bluish colour is related to sediments. The bright streaks oriented NE-SW are related to wind forces.

This image has been selected for release because of the various details which give an insight into the erosional history of the outflow channel. The image also illustrates how difficult it is to achieve near-true colour in images of Mars when atmospheric dust and haze have a major disturbing influence on the scene.