Mapping Human Terrain

If you walk the hallways--that is, if you're escorted through the hallways--of the National Geospatial-Intelligence Agency in Bethesda, Md., you'll see some remarkable maps.

Based on photos taken from space, they depict cities, highways, farm fields, forests and rivers in exquisite detail and vivid color. But these are mere decorations compared with the highly detailed and highly classified images that geospatial analysts here study daily behind heavily bolted doors.

Working with satellite images, video shot by unmanned aerial vehicles and data collected from spy planes using a variety of other overhead sensors, NGA provides the U.S. armed services with maps, images and targeting analysis to guide military operations.