Exploratour - The Surface of Mars
Volcanoes
Mars has many volcanoes, and many of them are found on the Tharsis Ridge, including Olympus Mons, the biggest volcano in the solar system.
On this map of Mars, the Tharsis Ridge is shown, as well as the Martian highlands (near the bottom of the picture), and Valles Marineris to the right.
Olympus Mons is biggest red dot on the far left of the image. The other red spots are other volcanoes on Mars.