MAP READING
AND
LAND NAVIGATION
FM 21-26
DEFINITION OF A MAP
A MAP IS A GEOGRAPHIC REPRESENTATION OF
A PORTION OF THE EARTH’S SURFACE DRAWN
TO SCALE, AS SEEN FROM ABOVE.
IT’S USES COLORS, SYMBOLS
AND
LABELS TO REPRESENT FEATURES FOUND
ON THE GROUND.
PURPOSE OF A MAP
A MAP PROVIDES INFORMATION ON THE
EXSISTENCE OF, THE LOCATION OF, AND THE
DISTANCES BETWEEN GROUND FEATURES.
MAP SCALES
LARGE:
1:50,000
MEDIUM:
1: 100,000
SMALL:
1: 250,000
COLORS OF THE MAP
BLACK: MAN-MADE FEATURES, SUCH AS
BUILDINGS AND ROADS.
RED-BROWN: RELIEF FEATURES AND ELEVATION
(CONTOUR LINES ON RED-LIGHT READABLE MAPS).
BROWN: RELIEF FEATURES & ELEVATION
(CONTOUR LINES ON OLDER MAPS).
GREEN: VEGETATION (WOODS, ORCHARDS, VEGITATION).
BLUE: DRAINAGE (WATER).
RED: POPULATED AREAS, MAIN ROADS AND BOUNDARIES
ON OLDER MAPS.
TERRAIN FEATURES
• Five Major
Hidden Valley Ranch Salad Dressing
Hilltop, Valley, Ridge, Saddle, Depression
• Three Minor
Draw, Spur, Cliff
• Two Supplementary
Cut, Fill
HILL: AN AREA OF HIGH GROUND. FROM
A HILLTOP, THE GROUND SLOPE DOWN IN
ALL DIRECTIONS.
FM 21-26: PAGE 10-9 (FIGURE 10-17)
VALLEY: A STRETCHED-OUT GROOVE IN
THE LAND, USUALLY FORMED BY
STREAMS OR RIVERS.
FM 21-26: PAGE 10-10 (FIGURE 10-19)
RIDGE: A SLOPING LINE OF HIGH GROUND.
FM 21-26: PAGE 10-11 (FIGURE 10-20)
SADDLE: A DIP OR LOW POINT BETWEEN
TWO AREAS OF HIGHER GROUND.
FM 21-26 PAGE 10-11 (FIGURE 10-18)
DEPRESSION: A LOW PO INT IN THE GROUND
OR SINKHOLE. THEY ARE REPRESENTED BY CLOSE
CONTOUR LINES THAT HAVE TICK MARKS POINTING
TOWARD LOW GROUND.
FM 21-26: PAGE 10-11 (FIGURE 10-21)
DRAW: A LESS DEVELOPED STEAM COURSE THAN A VALLEY.
THERE IS ESSENTIALLY NO LEVEL GROUND AND, THEREFORE,
LITTLE OR NO MANEUVER ROOM WITHIN ITS CONFINES.
FM 21-26: PAGE 10-12 (FIGURE 10-22)
SPUR: A SHORT, CONTINUOUS SLOPING LINE OF
HIGHER GROUND, NORMALLY JUTTING OUT FROM
THE SIDE OF A RIDGE.
FM 21-26: PAGE 10-12 (FIGURE 10-23)
CLIFF: A VERTICAL OR NEAR VERTICAL FEATURE; IT IS AN ABRUPT
CHANGE OF THE LAND. THE SLOPE IS SO STEEP THAT THE
CONTOUR LINES CONVERGE INTO ONE CONTOUR LINE OR THE LAST
CONTOUR LINE HAS TICK MARKS POINTING TO LOW GROUND.
FM 21-26: PAGE 10-13 (FIGURE 10-24A & B)
CUT: A MAN-MADE FEATURE RESULTIING FROM CUTTING
THROUGH RAISED GROUND, USUALLY TO FROM A LEVEL BED
FOR A ROAD OR RAILROAD TRACK.
FILL: A MAN-MADE FEATURE RESULTING FROM FILLING A LOW
AREA, USUALLY TO FORM A LEVEL BED FOR A ROAD OR RAILROAD TRACK.
STP21-1-SMCT PAGE 30 -31 (FIGURE4-5)
CONTOUR LINES
ELEVATION IN METERS
Three types of contour lines
Intermediate: Are contour lines located between two index lines.
Supplementary: Are contour lines placed to specify half of
the contour interval.
Index: Are major EXAMPLE:
elevation points and have the
CONTOUR INTERVAL 20 meters
elevation
number
written
withing the contour.
100m
120m 130m
and 140m
(ex.100m,200m,300m)
SUPPLEMENTARY CONTOURS 10meters
200
FINDING POINTS
• (Orient the map)
• Compass or Terrain Association
• (Compass Technique)
• Cheek and Center hold methods
• (Grid Coordinates)
• Grid Zone Designator (RP) and Number sequence
» FOUR DIGIT, SIX DIGIT or EIGHT DIGIT
• Remember RIGHT then UP
• DEAD RECKONING
Compass Technique
COMPASS TO CHEEK METHOD
CENTER HOLD METHOD
The
to cheek
Thecompass
Center hold
method
technique
is used
is much faster
but is
almost
exclusively
also less
precise. for
sighting and is the best
technique for this
purpose.
ORIENTING THE MAP
A MAP IS ORIENTED WHEN IT IS IN
A HORIZONTAL POSITION WITH
ITS NORTH/SOUTH
CORESPONDING TO
THE NORTH/ SOUTH
ON THE GROUND
MILITARY PROTRACTOR
BASE LINE
DEGREES
MILS
THE GTA 5-2-12 IS THE MOST
COMMONLY USED PROTRACTOR
FOR MAP READING.
FM 21-26: PAGE 6-4 & 6-5
(FIGURE 6-6 & 6-7)
INDEX
GRID COORDINATES
To locate any coordinate:
Must go RIGHT then UP
Four Digit Coordinate
Location Within 1000m
(RP5904)
GRID PRECISION
Six Digit Coordinates
Locate a point within
100 meters
Eight Digit Coordinates
Locate a point within
10 meters
RP59850432
VGT 5
VGT 7
Stations:
1) Shoot two azimuths, either in MILS or DEGS
using both methods.
2)a) Given a known point ID its 4-Digit or
8-Digit coordinate.
3) a) Find Pace Count.
b) Given a 4 digit and an 8 digit coordinate
plot both points and ID the Feature or structure.
TERRAIN
IDENTIFICATION TEST
TERRAIN FEATURES
• Five Major
Hilltop, Valley, Ridge, Saddle, Depression
• Three Minor
Draw, Spur, Cliff
• Two Supplementary
Cut, Fill