Mountain
Heights of mountains are typically measured above sea level. Using this metric, Mount Everest is the highest mountain on Earth, at . There are at least 100 mountains with heights of over above sea level, all of which are located in central and southern Asia. The highest mountains above sea level are generally not the highest above the surrounding terrain. There is no precise definition of surrounding base, but Denali, Mount Kilimanjaro and Nanga Parbat are possible candidates for the tallest mountain on land by this measure. The bases of mountain islands are below sea level, and given this consideration Mauna Kea ( above sea level) is the world's tallest mountain and volcano, rising about from the Pacific Ocean floor.
Mountaineering
In North America, Pikes Peak () in the Colorado Rockies (discovered in 1806) was first climbed by Edwin James and two others in 1820. Though lower than Pikes Peak, the heavily glaciated Fremont Peak () in Wyoming was thought to be the tallest mountain in the Rockies when it was first climbed by John C. Frémont and two others in 1842. Pico de Orizaba (), the tallest peak in Mexico and third tallest in North America, was first climbed by U.S. military personnel which included William F. Raynolds and a half dozen other climbers in 1848. Heavily glaciated and more technical climbs in North American were not achieved until the late 19th and early 20th centuries.