![]() ![]() ![]() USGS applications for finding elevations include the Elevation Point Query Service, Bulk Point Query Service, and the National Map Viewer spot elevation tool. However, many of these elevations are also from pre-GPS measurements, so are not necessarily the most recent or best-available elevation for any particular point. peak elevations is NOAA's National Geodetic Survey's data sheet collection. Therefore, US Topo maps do not show mountain peak or other spot elevations. No national dataset of high-accuracy spot elevations exists and no government agency has a mandate to create one. Today, the Global Positioning System (GPS) delivers comparable accuracy on inexpensive consumer devices, and professional GPS equipment can achieve accuracies better than one foot (however, unlike some traditional triangulation methods, GPS measurements require visiting the point). Their average accuracy was on the rough order of +/- 10 feet, though accuracy varied with method, terrain, and map vintage. These elevations were usually measured either by field survey triangulation or photogrammetric triangulation. Historical USGS topographic maps (produced until 2006) included spot elevation labels on mountain peaks, local high points, and sometimes well defined points such as crossroads. Topographic maps Click on a map to view its topography, its elevation and its terrain. ![]()
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