It's not a mountain range in the traditional sense that we think of, as it's mostly underwater. This enormous system of underwater mountains stretches for over 40,000 miles (64,000 km) around the globe, making it longer than the Andes, the Rockies, and the Himalayas combined.

The Mid-Ocean Ridge is formed by tectonic plates pulling apart and allowing magma to rise and solidify, creating new ocean floor.