Glossary

The four main points of the compass: north, south, east, and west.

The figure on a map that shows orientation and the cardinal directions (north, south, east, and west).

The vertical difference between neighboring contour lines. Check the map margin for the interval and its units; a 20-foot interval means each adjacent contour represents 20 feet of elevation change.

Lines that connect points of equal elevation. Closely spaced contours indicate steep terrain; widely spaced contours indicate gentle slopes.

The height of a point above a reference level, commonly mean sea level. On a topographic map, labeled contours and spot heights help you read elevation.

A heavier contour line labeled with its elevation. It makes it easier to read heights and count the lighter contour lines between labeled lines.

A pair of coordinates that identifies a place on Earth. Latitude measures degrees north or south of the equator; longitude measures degrees east or west of the prime meridian.

The panel that explains what the map’s symbols, colors, and line styles represent.

The angle between true north and magnetic north at a particular place and time. It matters when using a magnetic compass with a map; use a current value for your location.

The differences in elevation across an area. Maps can show relief with contour lines, shaded terrain, or colors that represent different heights.

The ratio between a distance on the map and the corresponding distance on the ground (for example, 1:24,000). A larger scale shows more detail over a smaller area.

A detailed map that represents the shape and elevation of the land surface using contour lines and relief.