https://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf

istic of a topographic map is that the shape of the Earth's surface is shown by contour lines. Contours are imag- inary lines that join points of equal elevation on  ...

https://www.usgs.gov/products/maps/topo-maps

These are general-use maps at medium scales that present elevation (contour lines), hydrography, geographic place names, and a variety of cultural features.

https://pubs.usgs.gov/circ/1955/0368/report.pdf

Selection in mapping relief features . 9 a. Choosing a contour interval. 9 b. Generalization . . . . . . . . 10. 8. Topographic expression. 10. 9. Kinds of relief features.

http://www.uky.edu/KGS/gis/USGSTopoSymbols.pdf

County or State hasis, USGS quadrangle series maps cover areas bounded by ... contour interval is the elevation difference between adjacent contour lines.

http://nyfalls.com/maps/topographic-guide/

The 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 ...

https://www.nwcg.gov/course/ffm/mapping/55-contour-lines-and-intervals

A contour line is a line drawn on a topographic map to indicate ground elevation or depression. A contour interval is the vertical distance or difference in ...

http://geokov.com/education/topographic-maps-contour.aspx

Contour lines in topographic maps (topographic contours) are imaginery lines that ... In USGS topo maps bechmarks are indicatd with letters BM and black cross.

https://weather.gladstonefamily.net/topoweb/guide.html

For a list of additional USGS map symbols, go the the USGS Symbol Page. ... Contour lines are the continuous brown lines found on topographic maps that give ...

http://www.ussartf.org/topo_map_basics.htm

Contours are imaginary lines that join points of equal elevation on the ... by a set of standard symbols on all U.S. Geological Survey (USGS) topographic maps.

http://faculty.chemeketa.edu/afrank1/topo_maps/contour_interval.htm

Contour lines can be drawn for any elevation, but to simplify things, only lines for certain elevations are drawn on a topographic map. These elevations are ...