As an officer, you must be proficient in the art of military map reading. All operations that are in liaison with active and reserve military units will always use military maps in their execution and operations orders. You will be expected to have the skills necessary to follow those instructions. Refer to FM 21-26, Map Reading and Land Navigation.

Practical testing in map reading skills will be an important part of your OTC program. Areas of testing are:

  1. Identify uses of topographic symbols, colors, physical symbols, and marginal information on a military map, and how to determine location using grid coordinates.
  2. Measure distance using map scales.
  3. Determine direction using a map protractor.
  4. Determine direction without a compass.
  5. Locate your position using resection & modified resection.
  6. Contour lines and elevation.


The first thing you should know about a map is that it is nothing more than a drawing of a piece of the earth's surface as it would be seen from above looking straight down.

Your map shows much more than just terrain. It shows physical symbols for man-made objects such as roads, buildings, etc., and topographic symbols identifying terrain features. All of these objects are represented on the map by a symbol, and these symbols are explained in the lower left corner of every map in a section called the LEGEND. Learn how to use the Legend.

The Legend also gives you information about the color codes used on the map. Know what the colors are and what they represent. Finally, the map also gives you crucial information in its margins, such as scale, date of printing, and in the bottom margin the Grid/Magnetic angle (difference between magnetic north, map grid north, and true north for your map.


There are no street addresses on your map, but you can still find your LOCATION accurately. Your map has black lines running up and down (North and South) and crosswise (East and West). Together they form squares called GRID SQUARES. Their lines are numbered along the outside edges of the map. Each grid Square has a different number. To get the correct number for a certain square, first read from left to right along the bottom edge of the map and find the line that borders the left side of your grid. Then read UP and find the East-West line that is the bottom border of your grid square. In other words, read RIGHT then UP. Using your map protractor, determine a six-digit grid coordinate to locate a point on the ground within 100 meters. Then determine an eight-digit grid coordinate to locate a point on the ground to within 10 meters. Record the grid coordinates with the correct two-letter grid square identifier. Refer to FM 21-26.


You can also use your map to measure distance between two places. Your map has been drawn to scale, meaning that a certain distance on the map equals a certain distance on the surface of the ground. The Map Scale is printed at the TOP and BOTTOM of your map; Example: Scale 1:50,000. This means that 1 inch on your map equals 50,000 inches on the ground. There are 36 inches per yard, 39.37 inches per meter, 3,600 inches per 100 yards, and 63,360 inches per mile. Refer to FM 21-26 for detailed methods for using all three of the map scales used on every military map.


The top of your map is ALWAYS at Grid North. The right edge of the map is always East, the bottom edge South and the left edge West. The vertical grid lines are always Grid N-S. The direction from one point to another, either on the map or along the ground, is the AZIMUTH. Azimuths are given in degrees from 1 to 360 in a clockwise direction beginning at North, or in mils from 0 to 6400. Since there are 360 degrees in a circle, your azimuth can be any number from 1 to 360. Due East is 90 degrees, due South is 180 degrees, due West 270 degrees and due North is 360 degrees. To get the right azimuth off a map you must use a protractor. Refer to FM 21-26 for directions for using a protractor to determine azimuth direction on your map.


When you have no compass, use the sun or stars to find your direction. You probably remember the old rule that "the sun rises in the East and sets in the West." It's not quite right. Unless you're on the equator, the sun doesn't rise due East and set due West--and where it does rise varies depending on the time of the year. Here are some methods for finding North.

A. Shadow-tip method

At a level spot, place a stick into the ground vertically so it casts a distinct shadow. Mark the shadow's tip with a stone see in figure). Wait 10 minutes or more and mark the new position with a second stone, then draw a line through the centers of the two stones. This drawn line is an EAST-WEST line. The first stone that you put down is WEST and the second is EAST.

Now draw a vertical line perpendicular to the EAST-WEST line to give you the NORTH-SOUTH line (B). Do this by taking a stick, hold one end of it on the West end of the line, and draw two arcs above and below the E-W line (see B in the fig-ure). Then hold the stick on the East end of the line and draw two arcs above and below the E-W line, intersecting the first two arcs. If you draw a straight line between the two arc intersections, this will be the N-S line.

B. Direction with your watch

Direction with your watch: You can also find direction with your watch, but not as accurately as the shadow-tip method. Point the hour hand at the sun. South will be half way between the hour hand and twelve o'clock.

C. North Star:

You can locate north at night by finding the North Star. Find the Big Dipper. The last two stars on the cup point directly at Polaris the North Star which is about five times as far out as the distance between those two stars in the cup. Facing the North Star, you are looking north with East on your right and West on your left.


Grid North, True North, and Magnetic North

The grid/magnetic angle in the lower margin of your map can be important to you. In many parts of the world your compass does not point due (grid) north, but varies some degrees right or left. The North-South lines on your map point the direction to Grid North. The needle of your compass always points to Magnetic North. Neither one points straight at the North Pole. The Grid/Magnetic angle in the map margin tells you how much they vary.


What if you want to locate your position but don't know exactly where you are?


Resection is computing your location by determining the back azimuth from two or more known points that you can see. Orient the left edge of your map to point North as closely as you can by using one of the methods listed above--then look around you for some feature that you can identify on the ground and on the map, i.e., a water tower.

Take a bearing (azimuth) to the water tower, and calculate the reverse bearing, or back azimuth. Place your protractor's center on the water tower symbol, and orient its top edge parallel to the East-West lines on the map. Mark a spot on the map at the protractor's edge where the reverse bearing is located. Draw a line from the tower symbol to tnd through that spot. Do the same with a second object you can see which is also on the map. Where the two lines cross is your location.

Alternately, GTA 5-2-13 has several methods of resection that you should be familiar with--study them.

Modified resection:

Modified resection works well when you know that you are already located on a feature, such as a road or a trail. You only need to take the back azimuth from a single object, say a school. You are located where the drawn back azimuth line crosses the feature you are on.


  1. Determine the type of terrain feature upon which you are located.
  2. Determine what types of terrain features surround your location.
  3. Orient your map by finding the group of terrain features on it.
  4. Determine the 4 cardinal directions (North, South, East, and West) by one of the methods above (i.e., using watcvh or sun shadow).
  5. Determine your location.


The brown lines on your map are called contour lines. Each line shows the height above sea level and is constant along its length. Contour lines never cross one another. Tick marks on lines always point down-slope. Printed at the bottom of your map is CONTOUR INTERVAL, which is the difference in height elevation between one brown line and the one next to it). The distance is usually 20 feet.

Every fifth line is printed heavier than the rest and has a number that gives the elevation of that line in feet. Find your position between the heavy brown contour lines and simply read the value, adding the lines as you close in on your position. GTA-5-2-13 has some good examples--study them.


Be able to identify the key terrain features--hills, valleys, saddles, depressions, cliffs and ridges as shown by contour lines on your map. Examples are shown in GTA-5-2-13.


color=#000000 Black: Indicates cultural (manmade) features such as buildings and smaller roads, trails (dashed lines), surveyed spot elevations, and all labels.
Red-Brown: On red light-readable maps, the colors red and brown are combined to identify cultural features, all relief features, nonsurveyed spot elevations, and elevation, such as contour lines.
Blue: Identifies hydrography or water features such as lakes, swamps, rivers, ditches, canals and drainage.
Green: Identifies vegetation with military significance, such as woods, orchards, swamps, windbreaks, vineyards and crops.
Brown: Identifies all relief features and elevation, such as contours on older edition maps, and cultivated land on red light-readable maps.
Red: Classifies cultural features, such as populated areas, built-up areas and cities, large (main) roads, and boundaries, on older maps.
Other: Occasionally other colors may be used to show special information, such as yellow for cities and towns. As a rule these are indicated in the marginal information.


Several kinds of general symbols appear on maps and are described in the map's legend.

Trees Green symbols, which may be organized in rows to illustrate an orchard or planted forest.
Roads Solid lines or red or black.
Unimproved roads Double dashed lines.
Trails Dotted lines.
Bridges Elongate brackets with wings on either side of a road or railroad.
Railroads Solid lines with small cross-lines.
Buildings Large ones are shown in black shapes, small ones as small squares. Churches have a small cross atop, and schools a small flag.
Towns Shown as a small black circle (small) or an outlined red circle (larger).
Cities Shown as a line-bounded area filled with pink or yellow.
Storage tanks Shown as a small or large circle with the contents as a label, i.e., Oil.
Towers Radio, TV, electrical towers are shown as a small black circle with a dot inside, and the word Tower alongside.
Power lines A series of spaced small circles connected by dashed lines.
Fences A series of spaced small Xes connected by straight lines.
Airports Shown with true runway shapes in black.
Elevations May be shown with the BM mark, or on smaller scale maps as simple spot elevation numbers with no symbol.


Military symbols usually consist of basic and interservice symbol, the unit size, the unit or installation role indicator, equipment indicator, aviation symbol and location, and the content of the fields surrounding the basic symbol. Geometric figures form the basic symbol used to represent units, installations and activities. Rectangle= a unit; Flag= a HQ; Circle= a logistical, medical, or administrative unit or depot. More information concerning symbols will be found in FM 101-5-1, Operational Terms and Graphics, or at Some typical unit symbols seen on a map:

Ideally, different colors are used to depict enemy and friendly symbols. Since different colors may not always be available, procedures for one-color and multicolor symbols are as follows: Friendly symbols are outlined by a single line; Enemy symbols with double lines. Blue or black indicates friendly units, posts, etc. not covered by other colors. Red indicates enemy elements. Yellow indicates chemical or radiological areas. Green indicates friendly and or enemy manmade obstacles. If other colors are used, they must be explained in a legend. (FM 101-5-1, Operational Terms and Graphics)


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