In selecting key terrain, the unit leader is beginning
are seldom completely dry. Water may change soil from
a hard, baked clay to slippery, impassable mud within a
to tie his mission to the ground. Inasmuch as key terrain
matter of minutes, especially in tropical areas. Another
features offer an advantage to one or both combatants,
aspect to consider, along with the types and condition of
it is apparent that the defender will strive to retain them
the soils, is the slope of the ground, the type of
while the attacker tries to seize them. For this reason,
vegetation, and the roughness of the surface.
key terrain is often assigned as the objectives of
attacking units; conversely, key terrain aids the defender
Cultural Features
in disposing his forces to best maintain his battle
position.
CULTURAL FEATURES include all the works of
Selection of key terrain features varies according to
man, such as towns, airfields, roads, railroads, and
the mission. In the attack, the unit leader selects key
bridges. For military purposes, man-made features are
terrain features forward of the line of departure. In the
considered an integral part of terrain. Cities and towns
defense, the terrain that must be held to maintain the
are frequently the objectives of an attacking force. For
integrity of the battle position is designated as key
tactical purposes, cultural features may be centers of
terrain.
resistance as well as physical obstacles in your path.
Roads, railroads, and bridges are vulnerable links in
Selection of key terrain also varies at the different
logistics and communication networks.
levels of command. For example, at force level, a large
city may offer a marked advantage as a communications
center or as a base for supply and maintenance facilities.
MILITARY ASPECTS OF TERRAIN
At division or regiment level, high ground dominating
Various combinations of weather and topography
the city may be important for observation and fields of
give certain qualities to an area. These qualities, known
fire. At battalion, company, and lower echelons, key
as the MILITARY ASPECTS OF TERRAIN, must be
terrain might be hills and valleys within the general high
closely evaluated by each unit leader. These qualities
ground around the city.
determine to a large degree how he employs his forces
and weapons. You can remember these military aspects
OBSERVATION AND FIELDS OF FIRE
of terrain by using the acronym KOCOA.
OBSERVATION of the battlefield is essential to
K Key terrain features
bring effective fire on the enemy, to control
O Observation and fields of fire
maneuvering of your troops, and to prevent being
C Cover and concealment
surprised by the enemy. Observation is classified as
either long or short range. Long-range observation is
O Obstacles
that which provides observation in excess of the
A Avenues of approach
effective range of small-arms fire (usually over 400
meters). Short-range observation covers the immediate
KEY TERRAIN FEATURES
foreground and extends to the effective range of
small-arms fire. Observation is limited or denied by
Key terrain is any locality or area that provides the
such factors as fog, heavy precipitation, heat refraction,
possessor a marked advantage over the enemy. Usually,
darkness, vegetation, cultural features, and relief.
the factors that make a feature or an area key terrain are
FIELDS OF FIRE are areas into which your
superior observation and fields of fire. Obstacles may
weapons can be fired effectively. An ideal field of fire
be considered key terrain when their possession by one
for the defense would be gentle sloping ground, fitted to
force prevents the movement of the opposing force. In
the trajectory of your weapons, and on which the enemy
some areas, such as mountains and jungles, where
can be seen with no protection from your fire. This
movement depends on established roads and paths,
situation is rarely encountered. However, you can
routes of communications could be key terrain. A bridge
improve the natural fields of fire by cutting or burning
over an unfoldable river could be key terrain,
weeds, grass, and crops; by clearing brush and trees; by
particularly when its seizure eliminates the need for an
demolishing buildings; and by cutting lanes through
assault crossing. An airfield could be key terrain when
woods. The commander must exercise caution in
its seizure facilitates the success of local operations or
serves as a base to support future operations.
ordering such work, since obviously constructed fire
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