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.
Mount Craig (North Carolina)
Formerly the third highest point in eastern North America, Mount Craig is currently designated by the USGS as the second. However, there is only a 4 foot (1.3 m) difference in elevation between it and 6,643-foot (2,025 m) Clingmans Dome, the highest point in the Great Smoky Mountains. Clingmans Dome's elevation is based on a conventional 1920 optical survey. Mount Craig's elevation was revised upwards in 1993 based upon satellite GPS to an accuracy of 4 inches (10 centimeters). Until Clingmans Dome can be remeasured by GPS, Mount Craig retains its designation as second highest.