Currently, There are at least 108 mountains on Earth with elevations of or greater above sea level. The vast majority of these mountains are located on the edge of the Indian and Eurasian plates in China, India, Nepal and Pakistan. The dividing line between a mountain with multiple peaks and separate mountains is not always clear (see also Highest unclimbed mountain). A popular and intuitive way to distinguish mountains from subsidiary peaks is by their height above the highest saddle connecting it to a higher summit, a measure called topographic prominence or re-ascent (the higher summit is called the "parent peak"). A common definition of a mountain is a summit with prominence. Alternatively, a relative prominence (prominence/height) is used (usually 7–8%) to reflect that in higher mountain ranges everything is on a larger scale. The table below lists the highest 100 summits with at least prominence, approximating a 7% relative prominence. A drawback of a prominence-based list is that it may exclude well-known or spectacular mountains that are connected via a high ridge to a taller summit, such as Eiger, Nuptse or Annapurna IV. A few such peaks and mountains with nearly sufficient prominence are included in this list, and given a rank of "S". It is very unlikely that all given heights are correct to the nearest metre; indeed, the sea level is often problematic to define when a mountain is remote from the sea. Different sources often differ by many metres, and the heights given below may well differ from those elsewhere in this encyclopedia. As an extreme example, Ulugh Muztagh on the north Tibetan Plateau is often listed as to , but appears to be only to . Some mountains differ by > on different maps, while even very thorough current measurements of Mount Everest range from to . These discrepancies serve to emphasize the uncertainties in the listed heights. Though some parts of the world, especially the most mountainous parts, have never been thoroughly mapped, it is unlikely that any mountains this high have been overlooked, because synthetic aperture radar can and has been used to measure elevations of most otherwise inaccessible places. Still, heights or prominences may be revised, so that the order of the list may change and even new mountains could enter the list over time. To be safe, the list has been extended to include all peaks. The highest mountains above sea