A caponier is a type of defensive structure in a

fortification A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere ...

. Fire from this point could cover the ditch beyond the curtain wall to deter any attempt to storm the wall. The word originates from the French ', meaning "chicken coop" (a ''

capon A capon (from la, cāpō, genitive ''cāpōnis'') is a cockerel ( rooster) that has been castrated or neutered, either physically or chemically, to improve the quality of its flesh for food, and, in some countries like Spain, fattened by for ...

'' is a castrated male chicken). In some types of

bastion A bastion or bulwark is a structure projecting outward from the curtain wall of a fortification, most commonly angular in shape and positioned at the corners of the fort. The fully developed bastion consists of two faces and two flanks, with fi ...

ed fortifications, the caponier served as a means of access to the outworks, protecting troops from direct fire; they were often roofless. Although they could be used for firing along the ditch, the flanks of the bastions were the main defence of the ditch by fire. In later

polygonal fort A polygonal fort is a type of fortification originating in France in the late 18th century and fully developed in Germany in the first half of the 19th century. Unlike earlier forts, polygonal forts had no bastions, which had proved to be vulnerabl ...

s, caponiers were often roofed, and were not intended as a type of ''

covered way In military architecture, a covertway or covered way (french: chemin couvert it, strada coperta) is a path on top of the counterscarp of a fortification. It is protected by an embankment which is made up by the crest of the glacis. It is able ...

'', but as the main way of keeping the ditch clear of the enemy.

History

Originally the term referred to a covered passageway that traversed the

ditch A ditch is a small to moderate divot created to channel water. A ditch can be used for drainage, to drain water from low-lying areas, alongside roadways or fields, or to channel water from a more distant source for plant irrigation. Ditches ar ...

outside the curtain of a

fortress A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...

. Fire from this point could cover the ditch beyond the curtain wall to deter any attempt to storm the wall. Thus the passageway was equipped with musket ports and

cannon A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...

ports that fired along the ditch. While fortifications were evolving to the simpler polygonal style, the term was sometimes used to describe the flanking positions set at the corners of the ditch that provide the same function in that style of fort, especially in France. In bastioned forts, it usually takes the form of a low open passage, often partly sunken into the floor of the ditch and projecting outward into and across it, with access from the main fortress via a passage through the curtain wall. The roof, if any, was often made against weather, observation, and small arms fire, not artillery. As polygonal fortresses evolved, caponiers became more substantial, higher, and protected above from plunging fire with masonry and earth cover. In late 19c. works which were largely underground, caponiers were reached via a tunnel from within the fort.

Equipment

The caponier is usually equipped with a firing step and

rifle A rifle is a long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves ( rifling) cut into the bore wall. In keeping with their focus on accuracy, rifles are typically designed to be held with ...

ports to allow troops to fire along the ditch, and often has provision for small cannon to sweep the ditch as well. To clear the smoke and fumes from the firing the roof of the caponier is often provided with ventilation ports. To avoid fire from one caponier bearing on the next, caponiers are sometimes set at alternate corners of the fort, so that they fire towards a blank wall at the opposite end of the ditch, giving full coverage of the ditch without subjecting the next caponier to fire. The length of the straight sections of the ditch is chosen so that it can be covered by fire from a single caponier. Caponiers are often wedge shaped so that they can fire down both angles of the ditch.

Counterscarp battery

An alternative to the caponier is a

counterscarp A scarp and a counterscarp are the inner and outer sides, respectively, of a ditch or moat used in fortifications. Attackers (if they have not bridged the ditch) must descend the counterscarp and ascend the scarp. In permanent fortifications th ...

battery, dug into the outer face of the corner of the ditch, giving a similar

field of fire The field of fire of a weapon (or group of weapons) is the area around it that can easily and effectively be reached by gunfire. The term 'field of fire' is mostly used in reference to machine guns. Their fields of fire incorporate the beaten zon ...

. Reached by a tunnel from within the fort, it does not have the vulnerable roof that the caponier has, but being outside the ditch, is potentially more vulnerable to

mining Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the econom ...

. Both structures may be found in the same fort.

Locations of caponiers

Caponiers are a common feature of 18- and 19th-century fortifications, and are found on almost all the Victorian forts of Malta, the

Palmerston Forts The Palmerston Forts are a group of forts and associated structures around the coasts of the United Kingdom and Ireland. The forts were built during the Victorian period on the recommendations of the 1860 Royal Commission on the Defence of the ...

in UK, the Lisbon Entrenched Camp forts in

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of th ...

, fortifications in many

Nordic countries The Nordic countries (also known as the Nordics or ''Norden''; lit. 'the North') are a geographical and cultural region in Northern Europe and the North Atlantic. It includes the sovereign states of Denmark, Finland, Iceland, Norway and Sw ...

, and in: *

Birgu Birgu ( mt, Il-Birgu , it, Vittoriosa), also known by its title Città Vittoriosa ("''Victorious City''"), is an old fortified city on the south side of the Grand Harbour in the South Eastern Region of Malta. The city occupies a promontory of ...

main ditch *

Fort Manoel Fort Manoel ( mt, Forti Manoel or ''Fortizza Manoel'') is a star fort on Manoel Island in Gżira, Malta. It was built in the 18th century by the Order of Saint John, during the reign of Grand Master António Manoel de Vilhena, after whom it ...

Fort Ricasoli Fort Ricasoli ( mt, Forti Rikażli) is a bastioned fort in Kalkara, Malta, which was built by the Order of Saint John between 1670 and 1698. The fort occupies a promontory known as Gallows' Point and the north shore of Rinella Bay, commanding th ...

Boden Fortress Boden Fortress ( sv, Bodens fästning) is a modern fortress consisting of several major and minor forts and fortifications surrounding the city of Boden, Norrbotten, in northern Sweden. The fortress was originally intended to stop or delay attack ...

in Sweden * Brest-Litovsk fortress, * Camden Fort Meagher, Crosshaven, Cork Harbour, Ireland * Coalhouse Fort,

Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...

, England *

Craignethan Castle Craignethan Castle is a ruined castle in South Lanarkshire, Scotland. It is located above the River Nethan, a tributary of the River Clyde, at . The castle is two miles west of the village of Crossford, and 4.5 miles north-west of Lanark. Built ...

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to ...

contains a good 16th century example. * Eluanbi Lighthouse in southern

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the no ...

Fort Glanville Conservation Park Fort Glanville Conservation Park is a protected area located in the Australian state of South Australia located in Semaphore Park, a seaside suburb of Adelaide consisting of a functional 19th century fort listed on the South Australian Heritage ...

Adelaide Adelaide ( ) is the capital city of South Australia, the state's largest city and the fifth-most populous city in Australia. "Adelaide" may refer to either Greater Adelaide (including the Adelaide Hills) or the Adelaide city centre. The dem ...

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest o ...

* Fort Hamilton,

New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

, USA *

Fort McClary Fort McClary is a former defensive fortification of the United States military located along the southern coast at Kittery Point, Maine at the mouth of the Piscataqua River. It was used throughout the 19th century to protect approaches to the ha ...

, Kittery Point, Maine *

Fort Thüngen Fort Thüngen is a historic fortification in Luxembourg City, in southern Luxembourg. It is sited in Dräi Eechelen Park, in the Kirchberg quarter, in the north-east of the city. It is also colloquially known as Three Acorns (, , ) in refer ...

, Luxembourg * Fort Washington,

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean t ...

, USA * Fort Wellington,

Prescott, Ontario Prescott, Ontario is a small town on the north shore of the Saint Lawrence River in the United Counties of Leeds and Grenville, Canada. In 2021, the town had a population of 4,078. The Ogdensburg–Prescott International Bridge, east of Presco ...

, Canada * Kyiv fortress *

Petersberg Citadel Petersberg Citadel (German:''Zitadelle Petersberg'') in Erfurt, central Germany, is one of the largest and best-preserved town fortresses in Europe.Stadtverwaltung Erfurt (17 November 2017) ''Petersberg'' Retrieved 23 December 2017 The citadel was ...

, Erfurt, Germany * Poznań Fortress,

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

Sevastopol Sevastopol (; uk, Севасто́поль, Sevastópolʹ, ; gkm, Σεβαστούπολις, Sevastoúpolis, ; crh, Акъя́р, Aqyár, ), sometimes written Sebastopol, is the largest city in Crimea, and a major port on the Black Sea ...

(

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inva ...

). *

Southsea Castle Southsea Castle, historically also known as Chaderton Castle, South Castle and Portsea Castle, is an artillery fort originally constructed by Henry VIII on Portsea Island, Hampshire, in 1544. It formed part of the King's Device programme to ...

Spandau Citadel The Spandau Citadel (german: Zitadelle Spandau) is a fortress in Berlin, Germany, one of the best-preserved Renaissance military structures of Europe. Built from 1559–94 atop a medieval fort on an island near the meeting of the Havel and ...

* Rhodes medieval town, Greece *

Suomenlinna Suomenlinna (; until 1918 Viapori, ), or Sveaborg (), is an inhabited sea fortress the Suomenlinna district is on eight islands of which six have been fortified; it is about 4 km southeast of the city center of Helsinki, the capital of Finl ...

in Finland *

York Redoubt York Redoubt is a redoubt situated on a bluff overlooking the entrance to Halifax Harbour at Ferguson's Cove, Nova Scotia, Canada, originally constructed in 1793. It was designated a National Historic Site of Canada in 1962. History York Redoub ...

and Fort Charlotte,

Halifax Regional Municipality Halifax is the capital and largest municipality of the Canadian province of Nova Scotia, and the largest municipality in Atlantic Canada. As of the 2021 Census, the municipal population was 439,819, with 348,634 people in its urban area. Th ...

, Canada * Newhaven Fort in East Sussex, UK * East Jiguanshan Fortress in Lüshun, Liaoning, China

Gallery

File:Fort Napoleon003.jpg, Caponier, Fort Napoleon, Ostend, Belgium File:RavelinAnselm 3.jpg, Caponier between the citadel wall and Ravelin Anselm,

, Germany File:Malta StLucian three.jpg, Caponier,

Fort San Lucian Fort San Lucian ( mt, Forti San Luċjan), also known as Saint Lucian Tower ( mt, Torri ta' San Luċjan) or Fort Rohan ( mt, Forti Rohan), is a large bastioned watchtower and polygonal fort in Marsaxlokk, Malta. The original tower was built by th ...

Malta Malta ( , , ), officially the Republic of Malta ( mt, Repubblika ta' Malta ), is an island country in the Mediterranean Sea. It consists of an archipelago, between Italy and Libya, and is often considered a part of Southern Europe. It lies ...

File:Malta Tas-Silg three.jpg, Caponier, Fort Tas-Silġ

File:Malta Tas-Silg six.jpg, Caponier, Fort Tas-Silġ

File:CapBF.jpg, Caponier,

Brest Fortress Brest Fortress ( be, Брэсцкая крэпасць, '; pl, Twierdza brzeska, russian: Брестская крепость), formerly known as Brest-Litoŭsk Fortress, is a 19th-century fortress in Brest, Belarus. In 1965, the title " ...

Belarus Belarus,, , ; alternatively and formerly known as Byelorussia (from Russian ). officially the Republic of Belarus,; rus, Республика Беларусь, Respublika Belarus. is a landlocked country in Eastern Europe. It is bordered by ...

File:Kraków - Wawel - Kaponiera 01.JPG, Caponier.

Wawel The Wawel Royal Castle (; ''Zamek Królewski na Wawelu'') and the Wawel Hill on which it sits constitute the most historically and culturally significant site in Poland. A fortified residency on the Vistula River in Kraków, it was established o ...

File:Scraesdon Fort - Caponier - geograph.org.uk - 345243.jpg, Caponier, Scraesdon Fort,

Cornwall Cornwall (; kw, Kernow ) is a Historic counties of England, historic county and Ceremonial counties of England, ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people ...

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...

File:Fort Prinz Karl - Saillantkaponniere (2007).jpg, Caponier, near Großmehring,

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

References

External links

Amherst Fort - Kent
{{Fortifications Fortification (architectural elements)