|Back to Table of Contents||Back to Theory Page||Forward to Page 2|
Prominence is a
term that represents the elevation of a summit relative to the
terrain. It is defined as the elevation of a summit relative to
the highest point to which one must descend before reascending to a
higher summit. There are several ways to describe this both
mathematically and conceptually.
Prominence is a
non-arbitrary first derivative
of elevation that quantifies a summit's height above all surrounding
terrain. Prominence is calculated as the
difference in elevation between a summit and the highest saddle that
that summit to any higher terrain.
A mountain with a prominence (P) value of 2,000 feet could be
rise at least 2,000 feet above all else.
Put another way, prominence is the elevation difference between the summit and the lowest contour that encircles it and no higher summit. It is the minimum height by which one would have to descend from a summit along a ridge in order to re-ascend to a higher peak.
Prominence describes the Relative Elevation value of a mountain summit.
All islands have a
at their highest point.  For
example, the summit of Mauna Kea is
the highest point on the island of Hawaii at an elevation of 13,796
feet. In order to ascend to a higher point
while staying on the surface of the
earth one would first have to descend to sea level, then re-ascend on
island or continent. Thus the summit of
Kea has 13,796' of prominence, the height by which this summit
all other points on the earth's surface manifold.
High points of islands and continents 
have elevations that equal their prominence.
Mauna Loa is the second highest summit on Hawaii. At 13,679' it is just 117' lower than Mauna Kea. Let's say that we could raise and lower the sea level at will. As the sea rose, the island of Hawaii would shrink in size until it was essentially dumbbell shaped: a pair of volcanoes. At 6,600' feet, the rising water would form a channel separating Mauna Loa from Mauna Kea at the low point of the ridge that connects the two volcanoes. At that moment Mauna Loa would be 7,079' above the new sea level; the mountain's prominence value.
The place where two "islands" separate is always a saddle, which is a low point on a ridge. In the case of Mauna Loa, the separation would occur at a place called Humuula Saddle (elevation 6,600'). We call Humuula the Key Saddle for Mauna Loa.
Every summit that is
not the high
point of an island or continent has a unique Key Saddle.
Every Key Saddle has a unique
summit. No saddle is a key saddle
for more than one summit.  As a rule
therefore, a given island or
continent will have a quantity of summits equal to the number of Key
plus one. 
Prominence turns out to be a convenient way to compare summits. Mountain climbers can use prominence to rank the importance of mountains. Prominence is also useful as a qualifying rule to determine inclusion of mountains on lists of summits.
Lists of the highest mountains have been around for at least 100 years. However, such lists have a classic shortcoming; how does a mountain qualify for inclusion on the list? In the absence of a qualifying rule, one might say that the earth's ten highest mountains are ten rocky outcrops on the Mt. Everest summit block. A list of high mountains must either employ a minimum prominence as a criterion or be based on a subjective sensibility as to what constitutes a separate peak (such as limiting entries to named peaks only).
This question of what constitutes a separate peak is a recurring one amongst mountain climbers. In Colorado, the generally accepted criterion for inclusion on lists is 300' of prominence. The 300' rule (sometimes referred to as the Colorado rule) is based on a 1950s survey of 14,000' mountains in Colorado published by the U.S.G.S. 
Prominence is also used extensively by British hillwalkers, both as a qualifying rule for high elevation summits and as a system of measurement unto itself. Alan Dawson (1992) published The Relative Hills of Britain, a list of every hill in Great Britain to P>500' . Several hikers have nearly completed this list.
Prominence is sometimes referred to as reascent, drop, shoulder drop, or saddle drop. The term itself was probably coined by Steve Fry, a Seattle-based mountaineer, in 1981. Fry published a series of articles proposing various measurements of mountains, such as prominence, steepness, and volume.  He also produced many early lists of prominent summits.
In the United States a group of a few dozen enthusiasts study the subject of prominence. Slowly the concept is gaining traction amongst the subculture of "peakbaggers".
The creation of prominence lists is significantly aided by a computer program called WinProm that extracts prominence data from digital elevation models.  WinProm's derives key saddles and summits from the terrain. Map checking must still be done thoroughly by hand.
A comprehensive index
of prominence lists worldwide can be found on the website www.peaklist.org.
volunteers have worked on various parts of prominence lists. In
the United States, a complete list of U.S. mountains to 2,000'
prominence (1,234 peaks) was
compiled by a diverse number of authors, most notably Andy Martin,
and Aaron Maizlish. Others who
have contributed significant effort are Jerry Brekhus, Jeff Howbert,
Mills, David Olson, John Roper, Roy Schweiker, and Ron
Howbert is near completion of a massive study of the 4,000+ summits in
Washington State with P>400'.. Aaron Maizlish has conducted similar research
Globally the greatest
amount of work has been done in Great Britain, where every hill with
P>150m has been chronicled and (with a few notable exceptions)
climbed. A team of Canadian researchers have mostly
cataloged Canadian summits at www.bivouac.com.
Bjørstad has produced detailed
lists of high-prominence summits for Norway and Sweden.
Metzler and Eberhard Jurgalski have researched prominence worldwide,
produced a provisional list of the 50 most
prominent summits on earth.
Finally, a group of
collaborators are in the process of identifying all summits on earth
with P>1,500m (4,921 ft.). There are approximately 1,530 of
the so-called ultra-prominences.
with the impressiveness and the local importance of major
As a result it
may be a better conceptual tool for visualizing the role of mountains
Earth's terrain than absolute elevation.
Take for example a side-by-side comparison of the lists of the
highest summits and most prominent summits
on earth. The first table lists 14
generally-accepted peaks with elevation >8,000 meters.
This list is confined to High Himalayan peaks.
Table 2 lists the 14 most
prominent summits. This list has a good geographical distribution
and includes all of the
famous "seven summits" - the highest points of the seven
In short, it is more
descriptive of the earth's
THE 14 HIGHEST MOUNTAINS ON EARTH COMPARED TO THE 14 MOST PROMINENT MOUNTAINS ON EARTH 
|Name:||Location:||Elev (ft.)||Prom (ft.)|
|1||Mt. Everest||High Point (HP) of World||29,035||29,035|
|2||Aconcagua||HP S. America||22,831||22,891|
|3||Mt. McKinley||HP N. America||20,320||20,138|
|4||Mt. Kilimanjaro||HP Africa||19,340||19,308|
|5||Cristobal Colon||(in Colombia)||18,947||18,320|
|6||Mt. Logan||HP Canada||19,550||17,224|
|7||Pico de Orizaba||HP Mexico||18,409||16,079|
|8||Vinson Massif||HP Antarctica||16,066||16,066|
|9||Puncak Jaya||HP New Guinea||16,023||16,023|
|10||Mt. Elbrus||HP Europe (Caucasus)||18,510||15,554|
|11||Mont Blanc||HP Europe (Alps)||15,774||15,403|
|13||Kluchevskaya Volcano||HP Kamchatka||15,584||15,252|
|14||Nanga Parbat||(in Pakistan)||26,657||15,118|
Prominence, as an independent system of measurement, significantly rewards the highest points of major mountain ranges and freestanding peaks. Volcanoes and island high points are well represented. Prominence is a "winner-take-all" measure in that the highest point of a natural feature is ascribed all of the vertical relief for that feature. Slightly lower peaks may have very low prominence if their relative elevation derives from their nearby higher neighbor.
Prominence is also independent of the specific terrain of the landform. A round, forested hill might have greater prominence, if it is surrounded on all sides by low-elevation terrain, than a jagged 14,000' alpine peak. Prominence simply represents the vertical discontinuity of both objects on the surface manifold in a mathematical fashion.
|Forward to Page 2|
|Back to Table of Contents||Back to Theory Page|