Finding Your Location (MGRS)

navigation_map_grid_squareTo avoid getting lost, you have to know how to find your location. There are no street addresses in a combat area. However, by using a military map, you can find your location without difficulty. Maps have black lines running up and down (north and south) and crosswise (east and west). These lines form small squares called “grid squares” that are numbered along the outside edge of the map picture. Using these numbers, you can identify each grid square.

No two squares have the same number. To get the right numbers for a certain grid square, read from left to right along the bottom and locate the line that borders the grid square on the left. Then read up and find the east-west line that borders the grid square along the bottom as shown in the image to the right.

the image to the right shows your location as grid square 1181. How do you know this? Start from the left and read right until you come to 11, and then read up to 81. Your location is somewhere in the grid square of 1181. Remember to read from left to right, then up.

Grid square 1181 gives your general location, but there is a lot of area inside that grid square. To make your location even more accurate, you will need to add another number to the first half and another to the last half.

To get these numbers, imagine that each grid square has ten lines inside it running north and south, and another ten lines running east and west. This makes 100 small squares. You can estimate where these imaginary lines are.

Suppose that you are halfway between line 11 and line 12. Your first added number is 5 and the first half of your location is 115. And suppose that you are also three tenths of the way between line 81 and line 82. Then the second half of the number is 813. (If you were exactly on line 81, the second half would be 810.)

The image below shows that if you were located where the dot is in grid square 1181, your location would be 115813.

navigation_grid_square_fig_4

These six numbers are called your “coordinates.” They give your location, and if you always know your coordinates, you can never be lost.

If you have GTA 5-2-12 (Coordinate Scale and Protractor), you do not have to worry about estimating where you are inside a certain grid square or use imaginary lines because you can determine your exact coordinates.

The coordinate scale and protractor is a square piece of clear, thin plastic—frequently called a “protractor” for short. The protractor helps to measure small distances inside grid squares. You can also measure angles with it. You will learn more about measuring angles later. Your squad leader can show you exactly how to use the protractor.

navigation_protractor

 

[Continue to Determining the Distance]

**Information adapted from the United States
(U.S.) Army Training Support Centers (TSCs)
Graphic Training Aid (GTA) GTA 05-02-013,
How To Avoid Getting Lost.