Trench warfareTrench warfare is the type of land warfare using occupied lines largely comprising military trenches, in which troops are well-protected from the enemy's small arms fire and are substantially sheltered from artillery. It became archetypically associated with World War I (1914–1918), when the Race to the Sea rapidly expanded trench use on the Western Front starting in September 1914. Trench warfare proliferated when a revolution in firepower was not matched by similar advances in mobility, resulting in a grueling form of warfare in which the defender held the advantage.
FenceA fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length. Alternatives to fencing include a ditch (sometimes filled with water, forming a moat).
World War IWorld War I or the First World War, often abbreviated as WWI or WW1, known contemporaneously as the Great War, was a major global conflict lasting from 1914 to 1918. It was fought between two coalitions, the Allies and the Central Powers. Fighting took place throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. The first decade of the 20th century saw increasing diplomatic tension between the European great powers.
Wire obstacleIn the military science of fortification, wire obstacles are defensive obstacles made from barbed wire, barbed tape or concertina wire. They are designed to disrupt, delay and generally slow down an attacking enemy. During the time that the attackers are slowed by the wire obstacle (or possibly deliberately channelled into killing zones, or both) they are easy to target with machine gun and artillery fire.
Screw picketA screw picket is a metal device which is used to secure objects to the ground. Today, screw pickets are used widely to temporarily "picket" dogs. They are also used to graze animals such as sheep, goats, and horses. Screw pickets are also used to stabilize small trees, tent poles, and other objects that are intended to remain upright. The original picket was a stake hammered into the ground to secure a horse by tying it to the stake. This required a second tool (a hammer) or the availability of a rock to use instead of a tool.
PrisonA prison, also known as a jail, gaol (dated, British and South African; historically used in Canada and Australia), penitentiary (North American English), detention center (or detention centre outside the US), correction center, correctional facility, lock-up, hoosegow or remand center, is a facility in which convicted criminals are confined involuntarily (against their will) and denied a variety of freedoms under the authority of the state as punishment for various crimes.
Agricultural fencingIn agriculture, fences are used to keep animals in or out of an area. They can be made from a wide variety of materials, depending on terrain, location and animals to be confined. Most agricultural fencing averages about high, and in some places, the height and construction of fences designed to hold livestock is mandated by law. A is the strip of land by a fence that is left uncultivated. It may be a hedgerow or a shelterbelt (windbreak) or a refugee for native plants. If not too narrow, it acts as a habitat corridor.
Concertina wireConcertina wire or Dannert wire is a type of barbed wire or razor wire that is formed in large coils which can be expanded like a concertina. In conjunction with plain barbed wire (and/or razor wire/tape) and steel pickets, it is most often used to form military-style wire obstacles. It is also used in non-military settings, such as when used in prison barriers, detention camps, riot control, or at international borders. During World War I, soldiers manufactured concertina wire themselves, using ordinary barbed wire.
Shrapnel shellShrapnel shells were anti-personnel artillery munitions which carried many individual bullets close to a target area and then ejected them to allow them to continue along the shell's trajectory and strike targets individually. They relied almost entirely on the shell's velocity for their lethality. The munition has been obsolete since the end of World War I for anti-personnel use; high-explosive shells superseded it for that role. The functioning and principles behind Shrapnel shells are fundamentally different from high-explosive shell fragmentation.
FortificationA fortification is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from Latin fortis ("strong") and facere ("to make"). From very early history to modern times, defensive walls have often been necessary for cities to survive in an ever-changing world of invasion and conquest. Some settlements in the Indus Valley Civilization were the first small cities to be fortified.
