An observation post, temporary or fixed, is a position from which soldier

Soldier

A soldier is a member of the land component of national armed forces; whereas a soldier hired for service in a foreign army would be termed a mercenary...

s can watch enemy movements, to warn of approaching soldiers (such as in trench warfare

Trench warfare

Trench warfare is a form of occupied fighting lines, consisting largely of trenches, in which troops are largely immune to the enemy's small arms fire and are substantially sheltered from artillery...

), or to direct artillery

Artillery

Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...

 fire. In strict military terminology, an observation post is any preselected position from which observations are to be made - this may include very temporary installations such as a vehicle parked as a roadside checkpoint, or even an airborne aircraft.

Operation

When selecting a (temporary) observation post, trained troops are to avoid obvious and conspicuous locations such as hilltops, water tower

Water tower

A water tower or elevated water tower is a large elevated drinking water storage container constructed to hold a water supply at a height sufficient to pressurize a water distribution system....

s or other isolated terrain features, and to assure that the observation post can be reached via a concealed

Concealment

Hiding is obscuring something from view or rendering it inconspicuous.Concealment is obscuring something from view or rendering it inconspicuous, the opposite of exposure...

 route. This is especially important as the observer in the post should be rotated every 20–30 minutes, as vigilance

Alertness

Alertness is the state of paying close and continuous attention, being watchful and prompt to meet danger or emergency, or being quick to perceive and act. It is related to psychology as well as to physiology...

 decreases markedly after such a time.

Observation posts should be manned with at least two personnel (more, for defense and observer rotation, if the post is to be retained for longer durations), and should be provided a means of communication with their chain of command

Chain of Command

Chain of Command may refer to:* Chain of command, in a military context, the line of authority and responsibility along which orders are passed* "Chain of Command" , the fifth episode of the first season of Beast Wars...

, preferably by phone instead of by radio.

Structure

Often being positioned in secret very close to the enemy, an observation post is usually a small construct, often consisting largely of camouflage

Military camouflage

Military camouflage is one of many means of deceiving an enemy. In practice, it is the application of colour and materials to battledress and military equipment to conceal them from visual observation. The French slang word camouflage came into common English usage during World War I when the...

 materials and maybe some weather cover. However, where frontlines

Front (military)

A military front or battlefront is a contested armed frontier between opposing forces. This can be a local or tactical front, or it can range to a theater...

 are expected to be stable for a longer time, an observation post (or ground observation post) may develop into a bunker

Bunker

A military bunker is a hardened shelter, often buried partly or fully underground, designed to protect the inhabitants from falling bombs or other attacks...

-like installation.

It is not unusual for soldiers to occupy a 'hide' for long periods of time. To avoid detection they have to remove all their own waste, this is achieved with the aid of clingfilm, plastic bags and empty water bottles.

One example of makeshift observation posts is Gaza Baptist Church

Gaza Baptist Church

The Gaza Baptist Church is a Baptist church in Gaza City, Gaza, Palestinian Territories. The Church is one of only three Christian churches in the Gaza Strip, and the only one that is Protestant and evangelical....

, which was commandeered by both Fatah

Fatah

Fataḥ is a major Palestinian political party and the largest faction of the Palestine Liberation Organization , a multi-party confederation. In Palestinian politics it is on the left-wing of the spectrum; it is mainly nationalist, although not predominantly socialist. Its official goals are found...

 and Hamas

Hamas

Hamas is the Palestinian Sunni Islamic or Islamist political party that governs the Gaza Strip. Hamas also has a military wing, the Izz ad-Din al-Qassam Brigades...

 troops during the Fatah–Hamas conflict

Fatah–Hamas conflict

The Fatah–Hamas conflict , also referred to as the Palestinian Civil War , and the Conflict of Brothers , i.e...

.