Important information is contained in a topographic map’s margins.
The 1:24,000-scale quadrangles, published by United States Geological Survey (USGS), are the standard topographic maps. The margins contain important information that is vital in reading the map.
The scale is located in the bottom margin of a topographic map. On a USGS map, the scale is given in feet and sections of a mile and kilometer.
The 1:24,000 scale map displays and an area of 7.5 minutes of both latitude and longitude, which is marked in the margins. Typically, the margins also contain Universal Transverse Mercator (UTM) coordinates in meters to pinpoint locations.
The bottom margin also displays magnetic and grid (true) north. The declination of magnetic north is important information for compass orienteering.
Contour interval, the elevation difference between lines, is given in the bottom margin. On the 1:24,000 scale map, contour intervals are usually ten feet.
The USGS notes that topographic maps are typically named by the most famous feature within the map. The name can be found in the top and bottom margins.
Dating Map Features
Topographic maps show house locations and other features. This information, along with the publication date printed in the margins, helps track development through time.