Obstacles to troop movement

Obstacles to troop movement represent either natural, human habitat originated, constructed, concealed obstacles, or obstructive impediments to movement of military troops and their vehicles, or to their visibility. By impeding strategic, operational or tactical manoeuvre, the obstacle represents an added barrier between opposing combat forces, and therefore prevent achievement of objectives and goals specified in the operational planning schedule. The constructed obstacles are used as an aid to defending a position or area as part of the general defensive plan of the commander. The obstacles that originate from the human habitat can be converted by troops into constructed obstacles by either performing additional construction, or executing demolitions to obstruct movement over the transport network, to create a choke point, or to deny traversing of an area to the enemy. The natural obstacles can be used defensively by securing a more difficult to breach defensive position by for example securing a flank on terrain that is deemed impossible to traverse, thus denying the enemy an ability to close into combat range of direct fire weapons.

Obstacles are used in combat operations to create choke points, deny mobility corridors and avenue of approach to positions, to enhance field of fire for direct fire weapons, or to protect key tactical terrain features to the enemy.

Natural obstacles are represented by those terrain features that for which few troops and their vehicles have capability to traverse. They include water obstacles, or areas of poor drainage such as lakes, rivers, swamps and marshes. The former two can be crossed by amphibious vehicles capable of swimming, or vehicles capable of deep wading after preparation, or by constructing a water crossing, and thus creating an easily targeted choke point. Soil and rock can also represent mobility obstacles if the soil is too soft and unable to support the weight of the military vehicles, or the terrain is fractured by cliffs, or large boulders that make organised movement impossible. While soft soil is relative to vehicle ground pressure, there is little that can be done to negotiate very rocky terrain or cliffs except by using specially trained light infantry troops. Vegetation such as jungles or dense forests can also represent obstacles to movement, in some cases even to light infantry troops. Some natural obstacles can be a result of climatic or soil activity such as deep snow that by covering all terrain makes safe traversing difficult and slow, or landslides that may create an obstruction suddenly despite previously clear route reconnaissance report.

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