Olympus Mons (Mars) – 24.9 km
The largest volcano on Mars is also the solar system's tallest mountain. It covers an area similar to the state of Arizona and is located near three other volcanoes known as the Tharsis Montes.
Rheasilvea Mons (Asteroid Vesta) - 21.2 km
Situated on the asteroid Vesta, it sits at the centre of a 480-kilometre-wide crater and is currently being studied by the spacecraft Dawn.
Equatorial Ridge of Iapetus (Saturn's moon) - 19.9 km
Saturn's moon Iapetus has a distinct equatorial ridge, with some peaks reaching over 12 miles high, giving it a unique appearance.
Ascraeus Mons (Mars) - 18.2 km
This Mars volcano is the tallest among the Tharsis Montes and has a central caldera that is 3.4 kilometres deep.
Boösaule Montes (Jupiter's moon Io) - 17.5 km
Boösaule Montes consists of three mountains on Jupiter's moon Io, with "South" being the tallest and exhibiting a steep slope.
Arsia Mons (Mars) - 15.1 km
The second-tallest volcano among the Tharsis Montes on Mars is believed to potentially host glaciers.
Pavonis Mons (Mars) - 14 km
The shortest among the Tharsis Montes is also thought to be a possible location for glaciers.
Elysium Mons (Mars) - 12.5 km
The tallest volcano in the Elysium Planitia on Mars, the second-largest volcanic system on the planet.