Mid-ocean

The mid-ocean ridge is the longest mountain range on Earth.

The mid-ocean range stretches around the globe like the seam of a baseball.

The longest mountain range on Earth is called the mid-ocean ridge. Spanning 40,389 miles around the globe, it's truly a global landmark.

About 90 percent of the mid-ocean ridge system is under the ocean.

About 90 percent of the mid-ocean ridge system is under the ocean. This system of mountains and valleys criss-crosses the globe, resembling the stitches in a baseball. It's formed by the movement of the Earth's tectonic plates.

If you look at a map of the world's volcanoes, you'll find that most of them form along the boundaries of this great system. In fact, the global mid-ocean ridge system forms the largest single volcanic feature on the Earth.

The mid-ocean ridge consists of thousands of individual volcanoes or volcanic ridge segments which periodically erupt.

Whence we come we know not; and whither we are going, who can tell? We float out our life in the mid-ocean, with the warm sunshine above our heads, and the warm gulf-stream below; and that is enough for us.