Map Reading and Land Navigation
TC 3-25.26 is the Army's map reading and land navigation manual: grids, marginal information, terrain features, azimuths, and navigation techniques. Dated November 2013, it is still the active reference used on land navigation courses and at boards. Note the designator -- it is a TC, not an FM or ATP.
Open the official record- Type
- TC
- Edition verified
- November 2013
- Used in
- TrainingBoard Prep
What to take from it
- A six-digit grid locates a point to within 100 meters; an eight-digit grid to within 10 meters.
- Three norths appear in the declination diagram: true north, magnetic north, and grid north.
- Five major terrain features: hill, valley, ridge, saddle, and depression.
- Covers converting between grid and magnetic azimuths using the G-M angle.
These points are our summary, written for recall. They are not a substitute for the publication and they will not cover everything a board can ask. Read the source.
Board questions from this publication
What are the three parts of a complete military grid reference system coordinate?
The grid zone designation, the 100,000-meter square identifier, and the numerical grid coordinate read to the required precision.
TC 3-25.26, Map Reading and Land Navigation
What is the rule for reading a grid coordinate?
Read right and up. Read the easting first, left to right along the bottom, then the northing, bottom to top. The digits are always split evenly between the two.
TC 3-25.26, Map Reading and Land Navigation
How precisely does a four-, six-, eight-, and ten-digit grid coordinate locate a point?
Four digits locate a point to within 1,000 meters, six digits to within 100 meters, eight digits to within 10 meters, and ten digits to within 1 meter.
TC 3-25.26, Map Reading and Land Navigation
What are the five major terrain features?
Hill, ridge, valley, saddle, and depression.
TC 3-25.26, Map Reading and Land Navigation
What are the three minor terrain features and the two supplementary terrain features?
The three minor terrain features are draw, spur, and cliff. The two supplementary terrain features are cut and fill, both of which are man-made.
TC 3-25.26, Map Reading and Land Navigation
What is the difference between a draw and a spur?
A draw is a less developed stream course where the ground slopes upward on three sides and downward in one direction; water drains through it. A spur is a short, sloping line of higher ground extending out from the side of a ridge; water drains away from it on both sides. On a map the contour lines of a draw point toward high ground and those of a spur point away from it.
TC 3-25.26, Map Reading and Land Navigation
What are the three norths shown on a military map?
True north, magnetic north, and grid north. They appear together in the declination diagram in the map margin. True north is shown by a star, grid north by the letters GN, and magnetic north by a half arrow.
TC 3-25.26, Map Reading and Land Navigation
What is the G-M angle?
The grid-magnetic angle: the angular difference between grid north and magnetic north for that map sheet. It is shown in the declination diagram along with the conversion instructions used to change a magnetic azimuth to a grid azimuth or the reverse. Always use the conversion notes printed on the sheet you are working from.
TC 3-25.26, Map Reading and Land Navigation