List of tallest mountains in the Solar System

This is a list of the tallest mountains in the Solar System. The tallest peak or peaks on worlds where significant mountains have been measured are given; 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. However, in 2011, the central peak of the crater Rheasilvia on the asteroid and protoplanet Vesta was found to be of comparable height.

The heights are given from base to peak, because there is no nonarbitrary equivalent to height above sea level on other worlds.

The following images are shown in order of decreasing base-to-peak height.

Central peak of Vesta's crater Rheasilvia, imaged by Dawn from 100,000 km

Olympus Mons on Mars as viewed from Viking 1 in 1978

Cassini image of Iapetus's equatorial ridge

Voyager 1 photo of Io's highest peak, Boösaule Montes "South"

Ascraeus Mons (THEMIS IR with MOLA altimetry, 3x vertical stretch), Mars

Io's Euboea Montes (below top left), Haemus Montes (lower right); north is left

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