The European Space Agencyʼs (ESA) Mars Express spacecraft took a picture of the surface of Mars, which looks like one of the deepest canyons in the world — the Grand Canyon in the United States.
This is stated in the ESA press release.
The image shows two cracks in the Martian crust that are part of the large Mariner Valley canyon system. This valley crosses Mars like the Grand Canyon crosses the United States.
The only difference is that the Mariner Valley is almost ten times longer, 20 times wider and five times deeper than the Grand Canyon.
Also visible in the photo are two trenches (slumps) that form part of the western Mariner Valley. To the left is the 840-kilometer-long Io Canyon, and to the right is the 805-kilometer-long Tithonium Chasma Canyon.