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Tactical Tools (Corporal's Course)

Terms in this set (145)

1. Hill
A hill is an area of high ground. From a hilltop, the ground slopes down in all directions.

A hill is shown on a map by contour lines forming concentric circles.

The inside of the smallest closed circle is the hilltop.


A valley is reasonably level ground bordered on the sides by higher ground. A valley may or may not contain a stream course.

Contour lines indicating a valley are U- or V-shaped and tend to parallel a stream before crossing it.

The closed end of the contour line (U or V) always points upstream or toward high ground.

A valley generally has maneuver room within its confines.


A ridge is a sloping line of high ground. Standing on the centerline of a ridge, you will normally have low ground in three directions and high ground in one direction with varying degrees of slope.

Contour lines forming a ridge tend to be U-shaped or V-shaped. The closed end of the contour lines points away from high ground.

Crossing a ridge at right angles, you will climb steeply to the crest and then descend steeply to the base.

When moving along the path of the ridge, depending on the geographic location, there may be an almost unnoticeable slope or a very obvious incline.


A saddle is a dip or low point between two areas of higher ground. If you are in a saddle, there is high ground in two opposite directions and lower ground in the other two directions.

Contour lines for a saddle typically resemble an hourglass.

A saddle is not necessarily the lower ground between two hilltops; it may be simply a dip or break along a level ridge crest.


A depression is a low point in the ground or a sinkhole. It could be described as an area of low ground surrounded by higher ground in all directions, or simply a hole in the ground.

Depressions are represented by closed contour lines that have tick marks pointing toward low ground.

Usually, only depressions that are equal to or greater than the contour interval will be shown.