The planet with the largest mountain is Mars. The mountain in question is Olympus Mons, which is an enormous shield volcano located in the western part of Mars' Tharsis region. It is the tallest mountain in the Solar System, standing at an impressive 22 kilometers (14 miles) above the surrounding plains.
Olympus Mons is not just the tallest mountain in the Solar System, it is also the largest. It is over 600 kilometers (373 miles) across, two and a half times larger than the largest volcano on Earth, Mauna Loa in Hawaii. It is so large that it is visible from Earth with a small telescope.
The mountain is believed to have formed from a hotspot in the Martian mantle, similar to the Hawaiian-Emperor chain on Earth. This hotspot is believed to have remained in the same location for millions of years, allowing the volcano to grow to its immense size.
The base of the mountain is surrounded by a series of concentric ridges and valleys, which are believed to be the result of lava flows over time. The mountain is also home to a number of calderas, as well as numerous lava flows on its flanks.
The summit of Olympus Mons is unusually flat and featureless, with no obvious evidence of volcanic activity at the summit. This is likely due to the fact that the volcano is so large that any eruptions would be spread over a large area, making the summit appear relatively unchanged.
Olympus Mons is an incredible geological feature, and one of the most impressive features of the Solar System. It is an awe-inspiring reminder of the power of nature, and of the potential of the universe.