The National Elevation Dataset (NED) is derived mainly from 10 meter to 30 meter high resolution, best quality digital elevation data covering the United States, Puerto Rico, and the Virgin Islands. This is a seamless product updated bimonthly to incorporate the best available Digital Elevation Model (DEM)-a digital representation of cartographic information. NED is available in spatial resolutions of 1 arc-second (roughly 30 meters), 1/3 arc-second (roughly 10 meters), and 1/9 arc-second (roughly 3 meters).

NED 1 arc-second covers the conterminous United States, Hawaii, Puerto Rico, and the Virgin Islands. Alaska NED is at 2 arc-second or roughly 60 meters.

These digital elevation datasets are essential in understanding the Earth`s landscape: elevation, slope, and aspect (direction a slope faces.) NED is critical to identifying and modeling geologic features such as water drainage channels and basins, watersheds, peaks and pits, and land movements such as avalanches.

NED is used to create relief maps, 3-D visualizations, to classify land cover and to geometrically correct data from satellite or aircraft sensors (orthorectification). The fire community, natural resource managers, urban planners, conservationist, emergency responders, communication companies to name a few all rely on these elevation datasets.