The Topographic Map Legend

The Topographic Map Legend Explained

A. Here is where you find who created the map.

B. The title takes its name from the quadrangle (area the map covers).  All states are divide into rectangles (quadrangles) based upon the lines of longitude and latitude.  They are usually named for a town or prominent feature within the quadrangle.  The state and country are also given.

C. The USGS Categorizes Maps By Series According To How Much Land Is Covered- Represented By The Map.

D. Here you find the names of adjoining quadrangles. The names are in parentheses-  one at each corner and one on each side.

E.  Each corner is marked with its latitude and longitude.

F.  Every 2.5 minutes of latitude is marked by a fine black line along the right (Eastern) and left (Western) borders. Latitude in the North increases as you go North- toward the top of the map.

G. Every 2.5 minutes of longitude is marked by a fine black line along the top and bottom borders.  Longitude in the West increases as you go towards the left (West) side of the map.

H. Lines of latitude and longitude are indicated by crosses where they would intersect.

I. There may be other fine black marks on the border with such numbers as 690,000 feet.  These are part of the states plane coordinate system.

J. The fine blue lines along the borders are known as  Universal Transverse Mercator ( UTM ) Grid Ticks- Used For An International Scale.  Each One Is separated by one kilometer (or five-eighths of a mile)- a handy scale for you to use.

K. This block of information lets you know who did what,  how they did it,  and how the map was and when made.

L.  Revised information on a map is in purple.

M. Another title block with the quadrangles name, state, key latitude and longitude,  and amp series.  Also the dates of the last update.

N. Some maps show a key to road symbols.

O. The quadrangle location indicates its position within the state.

P.  The scale- tells you information you need to figure distance, etc.

Q. The bar scale allows you to make scaled measurements in miles, feet, and kilometers.

R. Contour interval- is the vertical distance (the change in elevation) between the brown contour lines.  These are lines joining areas of equal height.

S. Lets you know how accurate the map is based upon the National Map Accuracy Standards.

T.  The declination diagram shows the direction to the Geographic North Pole (shown by a star,  pointing to the top of the globe ), the Magnetic North Pole ( MN,  which is where a compass points to ),  and the Grid North Pole GN