Mountains beyond mountains
The tallest mountain on Earth is Mount Everest in the Himalayas, at about 8.8 km tall. In contrast, Olympus Mons, a mountain found on Mars, is 25 km high. This massive mountain is also very wide, with a diameter of 602 km, it covers an area about the size of Arizona. (https://bbc.in/2MKA4d6, http://bit.ly/2LSk6rN)