An ultra-prominent peak, or Ultra for short, is a mountain summit with a topographic prominence of 1,500 metres (4,900 ft) or more; it is also called a P1500. The prominence of a peak is the minimum height of climb to the summit on any route from a higher peak, or from sea level if there is no higher peak. There are approximately 1,524 such peaks on Earth. Some well-known peaks, such as the Matterhorn and Eiger, are not Ultras because they are connected to higher mountains by high cols and therefore do not achieve enough topographic prominence.
The term "Ultra" originated with earth scientist Steve Fry, from his studies of the prominence of peaks in Washington in the 1980s. His original term was "ultra major mountain", referring to peaks with at least 1,500 metres (4,900 ft) of prominence.
Currently, 1,515 Ultras have been identified above sea level: 637 in Asia, 353 in North America, 209 in South America, 119 in Europe (including the Caucasus), 84 in Africa, 69 in Australasia and 39 in Antarctica.
Many of the world's largest mountains are Ultras, including Mount Everest, K2, Kilimanjaro, Mont Blanc, and Mount Olympus. On the other hand, others such as the Eiger and the Matterhorn are not Ultras because they do not have sufficient prominence. Many Ultras lie in rarely visited and inhospitable parts of the world, including 39 in Greenland, the high points of the Arctic islands of Novaya Zemlya, Jan Mayen and Spitsbergen, and many of the peaks of the Greater ranges of Asia. In British Columbia, some of the mountains listed do not even have generally recognized names.
Thirteen of the fourteen 8,000-metre summits are Ultras (the exception being Lhotse), and there are a further 64 Ultras over 7,000 metres (23,000 ft) in height. There are 90 Ultras with a prominence of over 3,000 metres (9,800 ft), but only 22 with more than 4,000 metres (13,000 ft) prominence.
A number of Ultras have yet to be climbed, with Sauyr Zhotasy, (possibly) Mount Siple, and Gangkar Puensum being the most likely candidates for the most prominent unclimbed mountain in the world.
All of the Seven Summits are Ultras by virtue of the fact that they are the high points of large landmasses. Each has its key col at or near sea level, resulting in a prominence value almost equal to its elevation.
Ultra: peaks with a minimum prominence/relative height of 1500m. Steve Fry coined the term Ultra in the USA in the 1980s. His original term was 'ultra major mountain'. There are no Ultra summits in Britain. Hall of Fame entry minimum is 15.