ultraprominence

Ultraprominence is a term used in physical geography and mountaineering to describe peaks that are highly independent from surrounding terrain. It refers to the topographic prominence of a summit, which is the height of the peak above the lowest point on the ridge connecting it to a higher summit. This lowest point is called the key saddle or key col; the difference in elevation between the summit and the key saddle defines the prominence of the peak.

Ultraprominence is typically defined as a prominence of at least 1,500 meters (about 4,921 feet). Peaks meeting or exceeding this threshold are commonly called ultras. The 1,500 m criterion is widely used in global catalogs and mountaineering literature, though some regional lists employ slightly different cutoffs or incorporate additional considerations such as isolation or climber convention.

Determination of prominence relies on accurate topographic data, and the designation of a peak as ultra can depend on data quality and the method used to identify the key saddle. Ultras tend to be concentrated in rugged, tectonically active regions with deep valleys and long ridges, such as the Himalayas, Andes, Alaska Range, and parts of Africa and Oceania.

The ultras are valuable for ranking peaks by independence and for navigational planning. They include some of the planet’s most famous mountains, underscoring the dramatic relief that separates high summits from their surroundings. The concept emphasizes topographic, rather than merely elevational, distinctiveness.