Ogden, Utah - 7.5 Minute Series Topo Map National Audubon Society Backpacker magazine's Using a GPS

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On the basis of measurements

Preceded only by Lewis and Clark

Political boundaries are clearly defined

Ogden, Utah - 7.5 Minute Series Topo Map National Audubon Society Backpacker magazine's Using a GPSThe distinctive characteristic of a topographic map is that the shape of the Earth's surface is shown by contour lines. Contours are imaginary lines that join points of equal elevation on the surface of the land above or below a reference surface, such as mean sea level. Contours make it possible to measure the height of mountains, depths of the ocean bottom, and steepness of slopes. A topographic map shows more than contours. The map also includes