Contour Lines are imaginary lines on the Earth connecting points of equal elevation. They are shown in brown on standard U.S.G.S topographic maps. Elevations are given in feet or meters. Contours take some getting used to, but once you learn how to look at them they add a third dimension.

Contour lines bend upstream when they cross over streams, making a V-shape in the upstream direction. Closed contour lines, shown as ellipses or circles, represent hills. Closed contour lines shown with hacture marks, or short lines pointing downslope, represent a closed depression with no outlet. 

Contour lines enable you to find an elevation on a map, but to find a specific location, latitude and longitude, township and range lines are used.

Townships lines are used to show east and west boundaries. They contain Thiry-six sections and each section is divided into quarters.

Range lines are lines that run north and south and mark township boundaries.  

Latitude and Longitude

Latitude-longitude and township-range lines are used for giving locations.  Longitude is measured in degrees east and west, from the zero point or Prime Meridian. Latitude is measured in degress north and south from the zero point or the equator.  Latitude and longitude are broken into minutes and seconds, with one degree equal to sixty minutes, one minute equal to sixty seconds.

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