Valles Marineris: Quick Facts

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Nov. 10, 2026

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Mars: Valles Marineris

The western side of Candor Chasma, part of the Valles Marineris, Mars. The northern wall (top) shows evidence of having been affected by landslides, and the highly disturbed character of this region suggests considerable geological, and possibly hydrological, activity. This picture is a composite of high-resolution black-and-white and low-resolution colour images taken by the Viking 1 spacecraft.

Central Valles Marineris

Northern Valles Marineris, showing a section of Ophir Chasma. The 4-kilometre- (2.4-mile-) high chasm walls have been worn by erosion and gigantic landslides: the light area on the upper left is a landslide roughly 100 km (62 miles) wide. This picture is a composite of high-resolution black-and-white and low-resolution colour images taken by the Viking 1 and Viking 2 spacecraft.

Mosaic of more than 100 Viking orbiter photographs of Mars, showing most of a hemisphere centred near the equator and 80° W longitude. The large trough of the Valles Marineris extends from the Tharsis volcanoes on the west (left) eastward nearly 4,500 kilometres. White bands and streaks are water-ice clouds.

topographic map of Mars

Mars: Tharsis province

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Topics

Olympus Mons Tharsis Canals of Mars Utopia Planitia Maxwell Montes Chryse Planitia Vastitas Borealis Syrtis Major Nirgal Vallis Mare Orientale