All mountain heights and prominences on the list are from the largest-
scale maps available. However, heights often conflict on different topographic maps, even when created by the same cartographic institution. For example, the
Fletschhorn is indicated to be 3993, 3982, and 3984.5 m high on the 1:100,000, 1:50,000 and 1:25,000
Swisstopo map, respectively. This table uses the latter map's (rounded) elevation. Also, the deepest points in connecting ridges are not always survey points with spot elevations, where heights have to be estimated from contour lines. For example, maps often provide heights for where a route passes over a ridge rather than for the lowest point of that pass. Finally, many height indications on these maps are from quite old measurements, while glacier and
firn melt has decreased the height of both peaks and key cols, sometimes quite dramatically. For example, in 1930, glacier-capped
Cima Tosa was the highest mountain of the
Brenta Dolomites at 3,173 m, but now is around 3,140 m high and some 10 m lower than its rocky neighbor
Cima Brenta (3,151 m). Most maps and guides still report Cima Tosa's old height. On the other hand, in the 1930s, when the current Italian 1:25.000 topographic map of the region was created, the
Passo del Vannino, northwest of the
Ofenhorn, was covered by the
Lebendun glacier and was measured to be 2,754 m, while the much more recent Swisstopo map shows it to be bare and 2,717 m high. This is the key col for
Corno di Ban (3,028 m), which, thanks to the retreat of the glacier, now appears on the list with a prominence of 311 m. Given the inaccuracies, the list includes (unranked) summits with estimated prominences down to 7 meter below the cut-off (293 m), many of which may very well have a real prominence exceeding 300 m. ==Distribution==