Fortifications
Webpages concerning "Fortifications"
|
The contents has been generating using technology developed by scientec.
Wikipedia-Article "Fortifications"
- This article is about the military constructions. For other meanings of fort, fortress or fortification, see fort (disambiguation).
Fortifications are military constructions and buildings designed for defense in warfare. Humans have constructed defensive works for many thousands of years, in a variety of increasingly complex designs. The term is derived from the Latin fortis ("strong") and facere ("to make").
Many military installations are known as forts, although they are not always fortified. Larger forts may class as fortresses, smaller ones formerly often bore the name of fortalices. The word "fortification" can also refer to the practice of improving an area's defense with defensive works.
The art of laying out a military camp or constructing a fortification traditionally classes as castrametation, since the time of the Roman legions. The art/science of laying siege to a fortification and of destroying it has the popular name of siegecraft and the formal name of poliorcetics. In some texts this latter term also applies to the art of building a fortification.
Fortification is usually divided into two branches, namely permanent fortification and field fortification. Permanent fortifications are erected at leisure, with all the resources that a state can supply of constructive and mechanical skill, and are built of enduring materials. Field fortifications are extemporized by troops in the field, perhaps assisted by such local labor and tools as may be procurable, and with materials that do not require much preparation, such as earth, brushwood and light timber. There is also an intermediate branch known as semipermanent fortification. This is employed when in the course of a campaign it becomes desirable to protect some locality with the best imitation of permanent defences that can be made in a short time, ample resources and skilled civilian labor being available.
Medieval-style fortifications were largely made obsolete by the arrival of cannons on the 14th century battlefield. Fortifications in the age of blackpowder evolved into much lower structures with greater use of ditches and earth ramparts that would absorb and disperse the energy of cannon fire. Walls exposed to direct cannon fire were very vulnerable, so were sunk into ditches fronted by earth slopes. This placed a heavy emphasis on the geometry of the fortification to allow defensive cannonry interlocking fields of fire to cover all approaches to the lower and thus more vulnerable walls. Fortifications also extended in depth, with protected batteries for defensive cannonry, to allow them to engage attacking cannon to keep them at a distance and prevent them bearing directly on the vulnerable walls. The result was star shaped fortifications with tier upon tier of hornworks and bastions, of which Bourtange illustrated above is an excellent example. There are also extensive fortifications from this era in the Nordic states and in Britain, the fortifications of Berwick on Tweed being a fine example.
The arrival of explosive shells in the nineteenth centuary led to yet another stage in the evolution of fortification. Star forts of the cannon era did not fare well against the effects of high explosive, and the intricate arrangements of bastions, flanking batteries and the carefully constructed lines of fire for the defending cannon could be rapidly disrupted by explosive shells. Worse, the large open ditches surrounding forts of this type were an integral part of the defensive scheme, as was the covered way at the edge of the counter scarp. The ditch was extremely vulnerable to bombardment with explosive shells.
In response, military engineers evolved the polygonal style of fortification. The ditch became deep and vertically sided, cut directly into the native rock, layed out as a series of straight lines creating the central fortified area that gives this style of fortification its name.
Wide enough to be an impassable barrier for attacking troops, but narrow enough to be a difficult target for enemy shellfire, the ditch was swept by fire from defensive blockhouses set in the ditch as well as firing positions cut into the outer face of the ditch itself.
The profile of the fort became very low indeed, surrounded outside the ditch by a gently sloping open area so as to eliminate possible cover for enemy forces, while the fort itself provided a minimal target for enemy fire. The entrypoint became a sunken gatehouse in the inner face of the ditch, reached by a curving ramp that gave access to the gate via a rolling bridge that could be withdrawn into the gatehouse.
Much of the fort moved underground, with deep passages to connect the blockhouses and firing points in the ditch to the fort proper, with magazines and machine rooms deep under the surface.
The guns however were often mounted in open emplacements, simply protected by a parapet, both for a lower profile, and since experience with guns in closed casemates had seen them put out of action by rubble as their own casemates were collapsed around them.
Steel-and-concrete fortifications were common during the 19th and early 20th centuries, however the advances in modern warfare since World War I have made large-scale fortifications obsolete in most situations. Only underground bunkers are still able to provide some protection in modern wars. Many historical fortifications were demolished during the modern age, but a considerable number survive as popular tourist destinations and prominent local landmarks today.
Examples
See also
Fort components
- Abatis
- Barbed wire, Razor wire Wire entanglement, and Wire obstacle
- Czech hedgehog
- Pillbox
- Sandbag
- Turret
Types of forts
- Blockhouse
- Bunker
- Castle
- City wall
- Compound
- Keep
- Medieval fortification
- Pa a 19th century Maori fortification
- Polygonal fort
- Stockade
- Star fort
Historical Fortresses
- Atlantic Wall
- Bastle house
- Fort Knox, Maine
- Great Wall of China
- Kremlin
- Lines of Torres Vedras
- Maginot Line
- Martello tower
- Norwegian Fortresses
- Peel tower
Fortification and siege warfare
Famous experts
External links
- 1911 Encyclopedia Britannica on Fortifications and siegecraft
- Information on Australian World War 2 Fortifications
- A Military History of Malta (Fortifications)
- Bunker Pictures: Pictures, locations, information about bunkers from WW2 and The Atlantikwall
This article incorporates text from the 1911 Encyclopædia Britannica, which is in the public domain.