An ultra-prominent peak, or Ultra for short, is defined as a mountain summit with a topographic prominence of 1,500 metres (4,921 ft) or more. There are approximately 1,524 such peaks on Earth. Some 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" is due to earth scientist Stephen 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 5,000 ft (1,524 m) of prominence.
Currently, 1,515 Ultras have been identified worldwide: 637 in Asia, 355 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 136 in High Asia. In British Columbia, some of the mountains listed do not even have generally recognized names.