24:
443:
cross-checking among documents is sometimes needed to clarify the true assignments. For our sample fire control tower, the 6th floor ended up housing an observation post for the command of the northern guns defending Boston Harbor. The seventh floor held a base end station and a spotting station for
Battery 206, the pair of 6-inch (152 mm) guns nearby at East Point. The eighth floor was to have held a similar pair of stations for the two 16-inch (406 mm) guns at Fort Dawes on Deer Island, but those guns were never installed, so the use of the top floor is unclear. Also on the top floor was the "crow's nest" antiaircraft spotting post and its roof trapdoor.
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longer-range guns were developed and the superior accuracy of the horizontal baseline system of fire control was recognized, most major batteries (of 6-inch (152 mm) guns or larger) would be served by two, or sometimes three, base end/spotting stations. By WW2, longer-range guns required larger networks of base end and spotting stations, usually located in towers or cottages.
144:
observation level, and wooden ladders were then used to climb to higher levels. But some fire control structures built atop coastal hills or bluffs only needed to be one- or two-story buildings, and were built of wood or brick. Sometimes these buildings were camouflaged as private homes, and were referred to as fire control "cottages."
97:, known during WW2 as Site 131. Site 131-1A is on the right in this photo. Built in 1943-44, these twin towers watched over the northern approaches to Boston Harbor and directed the guns of several different Coast Artillery batteries. Towers similar to these can be found today in all coastal New England states.
497:
In the early days of the Coast
Artillery Corps (c. 1900-1915), most batteries would be controlled from a single vertical baseline fire control station located at the Battery Commander's position, in a nearby fire control building, or even in the concrete crow's nest of the battery casemate itself. As
189:
The length of the baselines running between each pair of stations was known very precisely. For example, Station #1 and
Station #2 were 12,249.63 yards (6.96 mi; 11.2 km) apart. These distances were plugged into the triangulation equations for the pair of stations involved in sighting on a
173:
Each major battery of Coast
Artillery guns was supported by a network of fire control structures (towers, cottages, or buildings) which were spread out along the nearby coast. Guns of longer range had larger numbers of fire control stations in their networks. Depending on where the target ship was
156:
Site 131-1A had electric lights, phones, and radio communications, and a time interval bell that was used for coordinating fire control information. Some fire control towers were also the mounting points for coast surveillance or fire control radar antennas. Although our sample tower has a simple,
143:
A fire control tower was usually five to ten stories tall, depending on the height of the site at which it was built and the area it had to cover. Often made of poured concrete, its lower floors were usually unoccupied and were capped by occupied observation levels. Staircases ran up to the lowest
116:
These towers were arrayed in networks along the coast on either side of the artillery batteries they supported. The number and height of the towers was determined by the range of the guns involved. Many fire control towers were also part of a harbor's antiaircraft warning system. Spotters occupied
152:
embedded in the tower's roof directly above this pad defined this point. Other observing instruments on lower floors of the tower were usually lined up directly beneath the eighth floor mounting pad and the rooftop marker, so they shared the same latitude and longitude. The pipe stands shown on
442:
The codes for the various batteries and command units at a given harbor could get confusing, since sometimes batteries were added or deleted and commands were reorganized between the time the plans were drawn up and the time the guns were mounted or the fire control towers were built. A lot of
418:
About 200 fire control towers once existed in the states of ME, NH, and MA alone, and perhaps 1,000 of these structures were built in the U.S. as a whole. Today, many of these towers have been demolished, but many others have survived, often on private property or in state or federal parks or
112:
For instance, the top story of Site 131-1A was planned to contain base end station #3 and spotting station #3 for
Battery #15. The overall plan document for the harbor defenses contained a list that linked the tactical numbers of all batteries to their names. That document also contained an
109:, or spotted the fall of fire from their battery, so the aim of the guns could be adjusted. For example, the fire control tower at Site 131-1A contained one OP, two base end stations, and two spotting stations. A shorthand notation was used to identify the stations.
177:
For a WW2-era example, take
Battery Murphy, the two 16-inch (406 mm) guns in Nahant, MA. Murphy used ten fire control stations that made up Battery Murphy's fire control network, which was spread out over about forty miles of coastline running from Station 1
190:
particular target in order to compute its position. As the target ship moved along the coast, different pairs of fire control stations (and therefore different baselines) would come into play. Very precise measurements were also taken of the distance between the
194:
of each battery (often the pintle center of its Gun #1) and each fire control station's observing point. These distance could also be used for target location, if one of the observations was taken from the battery itself and another from the distant station.
464:
received target coordinate data directly from observing instruments in fire control towers or from fire control radars and performed the triangulation calculations automatically. Gun data computers brought greater speed and accuracy to the fire control
432:
on Deer Island, were never finished, bringing the actual total number of batteries to 14. Depending upon the type of document being considered, however, these numbers might vary, contributing to confusion in describing the organization of the harbor
147:
The center of octagonal concrete mounting pad on the eight floor of 131-1A (which was meant to support a depression position finder) was usually the surveyed point at the end of the baseline (and thus the precise location of the base end station). A
132:. Since the distances along the line between the towers (called a baseline) had already been precisely measured by surveyors, the length of this baseline, plus the two bearing angles from two stations at the ends of the line (also called
474:
Sometimes (particularly early in the WW2 years) pre-existing structures, like water towers or seaside hotels featuring tall lookouts, were used as fire control towers. These installations were already naturally
354:
153:
floors six and seven of the Nahant Site 131-1A tower probably held azimuth scopes, which were less complex telescopes that determined bearings to a target but not its range from the tower.
1933:
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was used, the bearing angles and the baseline length from the two towers were input to the computer, where the triangulation equation was solved and firing data computed. If an older
460:
which were usually protected in earth-covered reinforced concrete bunkers or in the casemates of the larger gun batteries themselves. Later in the war, the electro-mechanical
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cramped "crow's nests" on the top floors of the towers that enabled them to lift a trapdoor in the tower's roof and scan the sky for approaching aircraft.
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located and upon other tactical conditions, one or more of these stations would be selected to control the fire from a given battery on that target.
62:
more complex. These towers were used in a number of countries' coastal defence systems through 1945, much later in a few cases such as Sweden. The
16:
This article is about a military structure to control the fire of coast artillery batteries. For a tower used to locate forest fires, see
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When an enemy surface craft was detected, bearings to it were measured from a pair of towers, using instruments like azimuth scopes or
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230:
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crew received bearing angles to the target from each station and then used the plotting board to calculate firing data for the guns.
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For Boston Harbor in WWII, 16 batteries of guns were initially planned. Two of the major batteries, Tactical Nos. 12 and 13 at
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is a structure located near the coastline, used to detect and locate enemy vessels offshore, direct fire upon them from
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A fire control tower usually contained several fire control stations, known variously as observation posts (OPs),
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105:, or spotting stations from which observers searched for enemy ships, fed data on target location to a
1973:
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square appearance, some versions of these towers in New
England had round or partly octagonal plans.
46:, or adjust the aim of guns by spotting shell splashes. Fire control towers came into general use in
1598:
2470:
1548:
186:) in the north. Half of these stations were located in tall towers, and half in low-rise cottages.
136:) to the target, could be used to plot the position of the target by a mathematical process called
360:
Former Harbor
Entrance Control Post-Harbor Defense Command Post disguised as a battleship bridge,
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systems in the late 19th century, as rapid development significantly increased the range of both
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was used to calculate firing data for coast artillery batteries. These devices were located in
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Composite view of 1904 East Side fire control structure at Ft. Andrews, Peddocks Island, MA
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organization chart that identified all the
Command (C) and Group (G) codes, like "G3."
17:
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Prior to WW2 (and sometimes throughout the war) a mechanical analog computer called a
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Map of the network of fire control structures serving
Battery Murphy in Nahant, MA
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included many fire control towers. These were introduced in the U.S. with the
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621:, similar large concrete towers built during WWII for anti-aircraft defense.
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Coast Artillery: Fire Control at the Coast Defense Study Group website
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554:(Third ed.). McLean, Virginia: CDSG Press. pp. 263–283.
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FM 4-15, Seacoast Artillery fire control and position finding
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Former Harbor Entrance Control Post disguised as a cottage,
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Former fire control tower resembling a lighthouse, Hull, MA
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Fire control tower at East Point MR Nahant, Massachusetts
81:, and were used between about 1900 and the end of WWII.
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A fire control tower at Ft. Monroe, VA (Destroyed 2001)
160:
93:
Two typical fire control towers on Swallow Cave Rd. in
70:during World War II included fire control towers.
124:Observing instruments used in fire control towers
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400:Emerson Point Fire Control Tower in Rockport MA
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552:American Seacoast Defenses, A Reference Guide
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292:Triangulation using two fire control towers
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212:A plan of all the floors of Nahant Site 1A
388:Utility Report for the Point Allerton FCT
332:, CA, modified as a hang glider platform
224:Elevation drawings of Nahant Site 131-1A
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119:
88:
22:
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549:
628:
614:Seacoast defense in the United States
260:A fire control tower at Ft. Miles, DE
484:The point surveyed was usually the "
272:Fire Control Tower 23, also part of
161:A network of fire control structures
2039:Weapons Storage and Security System
604:Coast Artillery fire control system
75:Coast Artillery fire control system
13:
654:
14:
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609:Coastal defence and fortification
304:Strawberry Point Base-End Station
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182:) in the south to Station 10 (
1:
1934:British "hedgehog" road block
550:Berhow, Mark A., ed. (2015).
526:
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85:A typical fire control tower
7:
2344:Cities with defensive walls
1929:Defensive fighting position
1844:
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1266:
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1223:
1214:
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581:
130:depression position finders
30:-era fire control tower at
10:
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488:center" of the instrument.
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15:
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1974:Hardened aircraft shelter
1949:Entry control point (ECP)
1861:
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913:
662:
590:, used to spot wild fires
328:Fire control position at
2471:Continuity of government
2293:Motte-and-bailey castle
1999:Missile launch facility
1994:Main line of resistance
689:
2565:Military installations
2369:Military installations
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2196:
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1785:
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1726:Scarp and Counterscarp
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68:German-occupied Europe
35:
2138:Floating water castle
1869:Admiralty scaffolding
1162:Fortified buildings (
168:
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95:Nahant, Massachusetts
92:
26:
2481:Subterranean warfare
1434:Viking ring fortress
2298:Quadrangular castle
2034:Weapon storage area
1390:Quadrangular castle
599:Fire-control system
2029:Underground hangar
1814:Fire control tower
1611:Gunpowder magazine
1039:Butter-churn tower
588:Fire lookout tower
574:2019-05-02 at the
171:
126:
99:
40:fire control tower
36:
18:fire lookout tower
2570:Coastal artillery
2552:
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2476:Military urbanism
2410:Fortified gateway
2283:Concentric castle
2047:
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1964:Fire support base
1804:Coastal artillery
1679:(Spanish America)
1273:
1115:Concentric castle
561:978-0-9748167-3-9
509:gun data computer
507:If a more modern
462:gun data computer
276:, but across the
134:base end stations
103:base end stations
56:coastal artillery
44:coastal batteries
2582:
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2540:
2534:
2425:National redoubt
2354:Fortified estate
2278:Circular rampart
2238:
2219:
2210:
2201:
2119:
1879:Anti-tank trench
1874:Air raid shelter
1849:
1809:Disappearing gun
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364:, New Castle, NH
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79:Endicott Program
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2191:Imperial castle
2164:Coercion castle
2159:Coastal defence
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2104:Promontory fort
2074:Hillside castle
2043:
1959:Fallout shelter
1924:Concertina wire
1904:Border security
1857:
1768:
1477:
1110:Coercion castle
1098:Cheval de frise
1080:Chemin de ronde
928:Albarrana tower
909:
854:Schwedenschanze
831:Promontory fort
658:
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576:Wayback Machine
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348:, Jamestown, RI
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48:coastal defence
32:Fort Saint Elmo
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2359:Fortifications
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2079:Hilltop castle
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1954:Electric fence
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1944:Dragon's teeth
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1939:Czech hedgehog
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1853:Wire obstacles
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1839:Polygonal fort
1836:
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1829:Martello tower
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1794:Border outpost
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1668:Polygonal fort
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1608:
1603:
1594:
1589:
1584:
1579:
1574:
1565:
1556:
1551:
1546:
1541:
1532:
1527:
1522:
1517:
1512:
1507:
1502:
1492:
1490:
1483:
1479:
1478:
1476:
1475:
1470:
1465:
1456:
1451:
1446:
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1436:
1431:
1426:
1421:
1416:
1411:
1402:
1397:
1392:
1387:
1382:
1377:
1372:
1367:
1362:
1357:
1352:
1347:
1342:
1337:
1332:
1327:
1322:
1317:
1312:
1307:
1298:
1293:
1288:
1279:
1274:
1254:
1249:
1244:
1239:
1234:
1229:
1220:
1211:
1206:
1197:
1192:
1187:
1180:
1175:
1160:
1158:Flanking tower
1155:
1146:
1137:
1132:
1127:
1125:Counter-castle
1122:
1117:
1112:
1107:
1102:
1093:
1084:
1075:
1066:
1061:
1056:
1051:
1046:
1041:
1036:
1031:
1026:
1021:
1012:
1007:
998:
989:
984:
979:
974:
969:
964:
959:
954:
949:
944:
935:
930:
925:
919:
917:
915:Post-classical
911:
910:
908:
907:
905:Vitrified fort
902:
890:
881:
872:
863:
858:
849:
844:
838:
833:
828:
823:
818:
809:
804:
795:
790:
785:
780:
775:
770:
765:
763:Defensive wall
760:
755:
750:
745:
740:
731:
722:
713:
704:
695:
686:
677:
672:
666:
664:
660:
659:
656:Fortifications
652:
651:
644:
637:
629:
623:
622:
616:
611:
606:
601:
596:
591:
583:
580:
579:
578:
566:
560:
544:
543:
531:
530:
528:
525:
522:
521:
515:was used, the
513:plotting board
500:
490:
477:
467:
458:plotting rooms
454:plotting board
445:
435:
421:
410:
409:
407:
404:
403:
402:
399:
392:
390:
387:
380:
378:
375:
368:
366:
359:
352:
350:
343:
336:
334:
327:
320:
318:
315:
308:
306:
303:
296:
294:
291:
284:
282:
271:
264:
262:
259:
252:
250:
247:
240:
238:
235:
228:
226:
223:
216:
214:
211:
204:
200:
197:
162:
159:
86:
83:
9:
6:
4:
3:
2:
2587:
2576:
2573:
2571:
2568:
2566:
2563:
2562:
2560:
2545:
2544:
2531:
2530:
2527:
2519:
2516:
2515:
2514:
2513:Urban warfare
2511:
2509:
2506:
2504:
2501:
2497:
2494:
2493:
2492:
2489:
2487:
2484:
2482:
2479:
2477:
2474:
2472:
2469:
2467:
2466:Civil defense
2464:
2463:
2461:
2457:
2451:
2448:
2446:
2443:
2441:
2438:
2436:
2433:
2431:
2428:
2426:
2423:
2421:
2418:
2416:
2413:
2411:
2408:
2406:
2403:
2401:
2398:
2396:
2393:
2391:
2388:
2387:
2385:
2381:
2375:
2372:
2370:
2367:
2365:
2362:
2360:
2357:
2355:
2352:
2350:
2347:
2345:
2342:
2340:
2337:
2335:
2334:Bastion forts
2332:
2331:
2329:
2325:
2319:
2318:Z-plan castle
2316:
2314:
2311:
2309:
2306:
2304:
2301:
2299:
2296:
2294:
2291:
2289:
2288:L-plan castle
2286:
2284:
2281:
2279:
2276:
2274:
2273:Bridge castle
2271:
2269:
2266:
2265:
2263:
2259:
2253:
2250:
2248:
2245:
2243:
2242:Refuge castle
2240:
2237:
2236:
2231:
2229:
2226:
2224:
2223:Military base
2221:
2218:
2217:
2212:
2209:
2208:
2203:
2200:
2199:
2194:
2192:
2189:
2187:
2186:Hunting lodge
2184:
2182:
2181:
2177:
2175:
2172:
2170:
2167:
2165:
2162:
2160:
2157:
2155:
2152:
2151:
2149:
2145:
2139:
2136:
2134:
2131:
2129:
2126:
2124:
2121:
2118:
2117:
2112:
2110:
2107:
2105:
2102:
2100:
2099:Moated castle
2097:
2095:
2092:
2090:
2087:
2085:
2084:Island castle
2082:
2080:
2077:
2075:
2072:
2070:
2067:
2065:
2062:
2060:
2057:
2056:
2054:
2052:By topography
2050:
2040:
2037:
2035:
2032:
2030:
2027:
2025:
2024:Submarine pen
2022:
2020:
2017:
2015:
2012:
2010:
2007:
2005:
2002:
2000:
1997:
1995:
1992:
1990:
1987:
1985:
1982:
1980:
1979:Hesco bastion
1977:
1975:
1972:
1970:
1967:
1965:
1962:
1960:
1957:
1955:
1952:
1950:
1947:
1945:
1942:
1940:
1937:
1935:
1932:
1930:
1927:
1925:
1922:
1920:
1917:
1915:
1912:
1910:
1907:
1905:
1902:
1900:
1897:
1895:
1894:Blast shelter
1892:
1890:
1887:
1885:
1882:
1880:
1877:
1875:
1872:
1870:
1867:
1866:
1864:
1860:
1854:
1851:
1848:
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1840:
1837:
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1827:
1825:
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1817:
1815:
1812:
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1807:
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1800:
1797:
1795:
1792:
1789:
1788:
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1781:
1778:
1777:
1775:
1771:
1764:
1763:
1758:
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1753:
1751:
1748:
1746:
1743:
1740:
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1734:
1732:
1729:
1727:
1724:
1722:
1719:
1717:
1714:
1712:
1709:
1707:
1704:
1701:
1700:
1695:
1692:
1691:
1686:
1684:
1681:
1677:
1676:
1671:
1669:
1666:
1664:
1663:Place-of-arms
1661:
1659:
1656:
1653:
1652:
1647:
1644:
1643:
1638:
1636:
1633:
1630:
1629:
1624:
1622:
1619:
1617:
1614:
1612:
1609:
1607:
1604:
1601:
1600:
1595:
1593:
1590:
1588:
1585:
1583:
1580:
1578:
1575:
1572:
1571:
1566:
1563:
1562:
1557:
1555:
1552:
1550:
1547:
1545:
1542:
1539:
1538:
1533:
1531:
1528:
1526:
1523:
1521:
1518:
1516:
1513:
1511:
1508:
1506:
1503:
1500:
1499:
1494:
1493:
1491:
1487:
1484:
1480:
1474:
1471:
1469:
1466:
1463:
1462:
1457:
1455:
1452:
1450:
1447:
1445:
1442:
1440:
1437:
1435:
1432:
1430:
1427:
1425:
1422:
1420:
1417:
1415:
1412:
1409:
1408:
1403:
1401:
1398:
1396:
1393:
1391:
1388:
1386:
1383:
1381:
1378:
1376:
1373:
1371:
1368:
1366:
1363:
1361:
1358:
1356:
1353:
1351:
1348:
1346:
1343:
1341:
1338:
1336:
1333:
1331:
1328:
1326:
1323:
1321:
1318:
1316:
1313:
1311:
1308:
1305:
1304:
1299:
1297:
1296:Machicolation
1294:
1292:
1291:L-plan castle
1289:
1286:
1285:
1280:
1278:
1275:
1270:
1269:
1261:
1260:
1255:
1253:
1250:
1248:
1245:
1243:
1240:
1238:
1235:
1233:
1230:
1227:
1226:
1221:
1218:
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1210:
1207:
1204:
1203:
1198:
1196:
1193:
1191:
1188:
1186:
1185:
1181:
1179:
1176:
1173:
1169:
1165:
1161:
1159:
1156:
1153:
1152:
1147:
1144:
1143:
1138:
1136:
1133:
1131:
1128:
1126:
1123:
1121:
1118:
1116:
1113:
1111:
1108:
1106:
1103:
1100:
1099:
1094:
1091:
1090:
1085:
1082:
1081:
1076:
1073:
1072:
1067:
1065:
1062:
1060:
1057:
1055:
1052:
1050:
1047:
1045:
1042:
1040:
1037:
1035:
1032:
1030:
1027:
1025:
1024:Bridge castle
1022:
1019:
1018:
1013:
1011:
1008:
1005:
1004:
999:
996:
995:
990:
988:
987:Bent entrance
985:
983:
980:
978:
975:
973:
972:Battery tower
970:
968:
965:
963:
960:
958:
955:
953:
950:
948:
945:
942:
941:
936:
934:
931:
929:
926:
924:
923:Advanced work
921:
920:
918:
916:
912:
906:
903:
899:
894:
891:
888:
887:
882:
879:
878:
873:
870:
869:
864:
862:
859:
856:
855:
850:
848:
847:Refuge castle
845:
842:
839:
837:
834:
832:
829:
827:
824:
822:
819:
816:
815:
810:
808:
805:
802:
801:
796:
794:
791:
789:
786:
784:
781:
779:
776:
774:
771:
769:
766:
764:
761:
759:
756:
754:
751:
749:
746:
744:
741:
738:
737:
732:
729:
728:
723:
720:
719:
714:
711:
710:
705:
702:
701:
696:
693:
692:
687:
684:
683:
678:
676:
673:
671:
668:
667:
665:
661:
657:
650:
645:
643:
638:
636:
631:
630:
627:
620:
617:
615:
612:
610:
607:
605:
602:
600:
597:
595:
592:
589:
586:
585:
577:
573:
570:
567:
563:
557:
553:
548:
547:
541:
536:
532:
518:
517:plotting room
514:
510:
504:
494:
487:
481:
471:
463:
459:
455:
449:
439:
431:
425:
419:reservations.
415:
411:
396:
391:
384:
379:
372:
367:
363:
356:
351:
347:
346:Fort Burnside
340:
335:
331:
324:
319:
312:
307:
300:
295:
288:
283:
280:in New Jersey
279:
275:
268:
263:
256:
251:
244:
239:
232:
227:
220:
215:
208:
203:
202:
196:
193:
187:
185:
181:
175:
167:
158:
154:
151:
150:survey marker
145:
141:
139:
138:triangulation
135:
131:
122:
118:
114:
110:
108:
107:plotting room
104:
96:
91:
82:
80:
76:
71:
69:
65:
64:Atlantic Wall
61:
57:
53:
49:
45:
41:
33:
29:
25:
19:
2536:
2491:Siege engine
2459:Other topics
2383:Related word
2349:Defense line
2313:Tower castle
2268:Bastion fort
2252:Urban castle
2180:Ganerbenburg
2178:
2133:Water castle
2109:Ridge castle
2094:Marsh castle
1909:Bomb shelter
1889:Belgian gate
1862:20th century
1813:
1773:19th century
1711:Retrenchment
1683:Punji sticks
1592:Entrenchment
1587:Device Forts
1554:Counterguard
1489:Early modern
1419:Tower castle
1355:Powder tower
1330:Outer bailey
1242:Inner bailey
1216:Gulyay-gorod
1184:Ganerbenburg
1182:
1178:Fujian tulou
1120:Corner tower
1059:Chamber gate
1029:Bridge tower
877:Trou de loup
551:
535:
503:
493:
480:
475:camouflaged.
470:
448:
438:
424:
414:
330:Fort Funston
278:Delaware Bay
188:
180:Fourth Cliff
176:
172:
155:
146:
142:
127:
115:
111:
100:
72:
60:fire control
58:. This made
39:
37:
28:World War II
2390:Castle town
2247:Toll castle
2216:Lustschloss
2198:Kaiserpfalz
2128:Spur castle
2123:Rock castle
2064:Hill castle
2059:Cave castle
2019:Spider hole
1919:Bremer wall
1884:Barbed tape
1780:Barbed wire
1454:Witch tower
1424:Tower house
1414:Toll castle
1400:Shield wall
1320:Murder hole
1209:Guard tower
826:Pincer gate
773:Faussebraye
184:Castle Hill
2559:Categories
2415:Gatekeeper
2235:Ordensburg
2207:Landesburg
2014:Sentry gun
1969:Flak tower
1899:Blast wall
1819:Gun turret
1716:Sally port
1621:Kotta mara
1561:Couvreface
1525:Breastwork
1520:Blockhouse
1498:Abwurfdach
1449:Watchtower
1439:Wall tower
1395:Shell keep
1345:Portcullis
1340:Peel tower
1325:Neck ditch
1284:Landesburg
1232:Half tower
1190:Gate tower
1135:Drawbridge
977:Battlement
893:Wagon fort
736:Chengqiang
619:Flak tower
527:References
430:Fort Dawes
362:Fort Stark
274:Fort Miles
52:naval guns
2518:Guerrilla
2261:By design
2009:Revetment
1824:Land mine
1755:Star fort
1582:Crownwork
1577:Covertway
1510:Barricade
1151:Embrasure
1064:Chartaque
994:Bergfried
952:Arrowslit
778:Gatehouse
748:City gate
709:Castellum
675:Acropolis
433:defenses.
406:Footnotes
73:The U.S.
2543:Category
2533:See also
2420:Loophole
2308:Ringwork
2303:Ringfort
2228:Obstacle
2069:Hillfort
1989:Loophole
1787:Barbette
1762:Tenaille
1745:Sea fort
1675:Presidio
1635:Magazine
1616:Hornwork
1549:Cavalier
1544:Casemate
1537:Caponier
1380:Ringwork
1268:Detinets
1237:Hoarding
1142:Enceinte
1017:Bretèche
962:Bartizan
957:Barbican
933:Alcazaba
861:Stockade
841:Ringfort
821:Palisade
793:Landwehr
788:Hillfort
582:See also
572:Archived
465:process.
2450:Vedette
2440:Schloss
2405:Festung
2400:Dungeon
2395:Château
2339:Castles
2147:By role
2004:Pillbox
1834:Outpost
1750:Station
1738:Schanze
1721:Sandbag
1706:Redoubt
1690:Ravelin
1658:Palanka
1642:Orillon
1628:Lunette
1570:Coupure
1515:Bastion
1505:Arsenal
1473:Zwinger
1385:Roundel
1375:Ricetto
1350:Postern
1335:Outwork
1259:Kremlin
1130:Curtain
1105:Citadel
1089:Chemise
1049:Caltrop
967:Bastion
940:Alcázar
836:Rampart
814:Oppidum
807:Nuraghe
753:Crannog
727:Castros
663:Ancient
199:Gallery
34:, Malta
2575:Towers
2445:Trench
2435:Picket
1846:Sangar
1799:Bunker
1731:Sconce
1651:Ostrog
1599:Flèche
1482:Modern
1461:Yagura
1429:Turret
1365:Reduit
1303:Merlon
1247:Kasbah
1225:Gusuku
1202:Glacis
1195:Gabion
1164:church
1071:Chashi
1054:Castle
898:Laager
886:Vallum
843:(Rath)
718:Castra
700:Burgus
670:Abatis
558:
486:pintle
2486:Siege
2430:Palas
2374:Walls
2364:Forts
2327:Lists
2174:Fence
2116:Rocca
1984:Kabal
1699:Redan
1606:Gorge
1530:Canal
1407:Shiro
1370:Ribat
1360:Qalat
1172:Dzong
1168:house
868:Sudis
800:Limes
758:Ditch
691:Broch
682:Agger
2496:list
1914:Buoy
1468:Yett
1310:Moat
1277:Ksar
1252:Keep
1044:Caer
1034:Burh
1010:Boom
1003:Berm
982:Bawn
947:Amba
783:Gord
556:ISBN
54:and
768:Dun
66:in
2561::
2535::
1170:,
1166:,
140:.
38:A
1272:)
1264:(
1174:)
901:)
895:(
648:e
641:t
634:v
564:.
178:(
20:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
