Denali or formerly Mount McKinley is North America's tallest mountain. It is located in South Alaska and its summit is 6,190 m above sea level. The topographic prominence of a mountain means the difference in elevation of the lowest point on a contour encircling the mountain (but not containing a higher peak within it) and it's summit. Denali is the third most prominent mountain in the world after Mount Everest and Aconcagua (the tallest peak in South America).