Usgs Topographic Map Viewer – For example, in the New York City area, elevations as of 2008 on USGS topographic maps were only surveyed to an accuracy of 10 feet. Along the Hudson River and some portions of Long Island . A topographic map uses markings such as contour lines (see page 00) to simulate the three-dimensional topography of the land on a two-dimensional map. In the U.S. these maps are usually U.S. .
Usgs Topographic Map Viewer Topographic Maps | U.S. Geological Survey: For example, in the New York City area, elevations as of 2008 on USGS topographic maps were only surveyed to an accuracy of 10 feet. Along the Hudson River and some portions of Long Island . A topographic map uses markings such as contour lines (see page 00) to simulate the three-dimensional topography of the land on a two-dimensional map. In the U.S. these maps are usually U.S. .