This image of the Arsia Mons shield volcano was taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express. The image was taken from an altitude of about 400 kilometres on 2 April 2004 during orbit 263 of the Mars Express spacecraft. This black and white image covers an area of 80 kilometres by 105 kilometres. The original image resolution was 20 metres per pixel, but the versions shown here have been reprocessed to reduce the volume of data for use on the internet.