which planet has the highest mountain and volcanoes in the solar system
Olympus Mons on Mars, the tallest planetary mountain in the Solar System, compared to Mount Everest and Mauna Kea on Earth (both elevations are sea-level-to-peak). This is a list of tallest mountains in the Solar System; in some cases, the tallest peaks of different classes on a world are also listed. At 21.9 km, the enormous shield volcano Olympus Mons on Mars is the tallest mountain on any planet. For 40 years, following its discovery in 1971, it was the tallest mountain known in the Solar System.