The phrase "USGS topographic map" can refer to maps with a wide range of scales, but the scale used for all modern USGS topographic maps is 1:24,000. Those will be added to more current maps over time. Older maps (published before 2006) show additional features such as trails, buildings, towns, mountain elevations, and survey control points. USGS topographic maps also show many other kinds of geographic features including roads, railroads, rivers, streams, lakes, boundaries, place or feature names, mountains, and much more. Contours make it possible to show the height and shape of mountains, the depths of the ocean bottom, and the steepness of slopes. ![]() ![]() Elevation contours are imaginary lines connecting points having the same elevation on the surface of the land above or below a reference surface, which is usually mean sea level. The distinctive characteristic of a topographic map is the use of elevation contour lines to show the shape of the Earth's surface.
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