Earth's Grand Canyon inspires awe for anyone who casts eyes upon the vast river-cut valley, but it would seem nothing more than a scratch next to the cavernous scar of Valles Marineris that marks the face of Mars. Stretching over 4000 km long and 200 km wide, and with a dizzying depth of 10 km, it is some ten times longer and five times deeper than Earth's Grand Canyon, a size that earns it the status of the largest canyon in the Solar System. Read more
Valles Marineris (Latin for Mariner Valleys, named after the Mariner 9 Mars orbiter of 1971-72 which discovered it) is a system that runs along the Martian surface east of the Tharsis region. At more than 4,000 km long, 200 km wide and up to 7 km deep, the Valles Marineris rift system is the largest known canyon, surpassing all canyons on Earth, with exception for the underwater deep rift valley that runs the 16,000 km length of the Mid-Atlantic Ridge. Read more