Here's why:

* Olympus Mons: This massive shield volcano on Mars is the largest known volcano in the solar system. It's about three times the height of Mount Everest and covers an area the size of Arizona.

* Valles Marineris: This canyon system stretches for over 4,000 kilometers (2,500 miles) and is up to 7 kilometers (4.3 miles) deep. It's so vast that it dwarfs the Grand Canyon in size.

While other planets have mountains and canyons, none surpass the sheer scale and depth found on Mars.