Reaching for the Sky
Mountains are some of the most awe-inspiring features on our planet, rising high above the surrounding land. Among them all, one peak stands tallest of all: Mount Everest. Its name has become a symbol for the ultimate challenge, the highest point a person can stand on the surface of the Earth.
The Roof of the World
Mount Everest reaches about 8,849 meters above sea level. That is nearly nine kilometers straight up into the sky, so high that the peak reaches into a zone where the air is too thin for people to breathe comfortably without help. Everest is part of the Himalayas, a great mountain range in Asia, and it sits right on the border between two countries, Nepal and China.
How a Mountain Is Measured
It is worth understanding what "highest" really means here. Everest is the highest mountain because its peak is the greatest distance above sea level. This is the standard way of comparing mountain heights. Using this measure, no other mountain on Earth reaches as high as Everest's summit. Its height was first established long ago by a major survey, and it has been measured again with modern technology since.
Highest Is Not the Only Way
Interestingly, "highest above sea level" is not the only way to think about a mountain's size. Measured from base to peak, a mountain in Hawaii called Mauna Kea is actually taller, but most of it is hidden underwater. And because the Earth bulges at the Equator, a peak in Ecuador is the farthest point from the Earth's center. Still, by the standard measure that everyone uses, elevation above sea level, Mount Everest remains the highest mountain in the world.
Source
This article was written using information from Wikipedia.