enemy installation iwo jima 1
TRANSCRIPT
EFENSE INSTALLATIOON IWO JIMA
Classification ch*ng*d to
ED
Maj., Inf. Custodian
CINCPAC-GINCPOABULLETIN NQ. 136-45
10 JUNE 1945
8 JUN1945
I
Defense Installations
on
I WO JIMA
flaintly
CINCPAC-CINCPOA
FLEET MARINE FORCE
V AMPHIBIOUS CORPS
3rd, 4th & 5th MARINE DIVISIONS
JICPOA L" 5 0 6 0 7 - 23 THRU 144
UNITED STATES PACIFIC FLEETAND PACIFIC OCEAN AREAS
MCH/cc HEADQUARTERS OF THE COMMANDER IN CHIEF
10 June 1945 - Serial DIS-1OO93O
From:To:
Subject:
Enclosure:
1.
Commander in Chief, U. S. Pacific Fleet and Pacific Ocean Areas.Distribution List.
CINCPAC-CINCPOA BULLETIN No. 136-45.Defense Installations on Iwo Jima.
(A) Subject bulletin.
Enclosure (A), forwarded herewith, need not be reported and when no. . _longer of value should be destroyed. No report of destruction is necessary.
M. LBpENDRE,By direction.
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10 June 1945 Serial DIS-1OO93O
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Table of Contents
JAPANESE DEFENSIVE PLAN AT IWO JIMA . . . . . 2-6
ILLUSTRATIONS . . 7-119General Terrain Features 7-16
Beaches . . . . . . . . . 7-10Terrain Inland * , 11-16
Obstacles and Mines 17-20Mines 17-18Trip Wire 19Anti-Tank Ditches • 20
Caves 21-25Coast Defense - Artillery 26-39
15 cm CD Guns 26-2614 cm CD Guns 29-3112 cm CD Guns 32-3312 cm (Short) Naval Guns 34-378 cm CD Guns 38-39
Antiaircraft and Dual Purpose Batteries 39-6412 cm DP Guns 39-4210 cm DP Guns 43-457 cm AA Guns 46-48
25 mm AA MG 49-5813 mm MG 59-60Searchlights . . . . . . . . 61-64
Blockhouses 65-70Covered Artillery Emplacements 71-86
120 mm Howitzers 71-7475 mm (Type 38) Field Guns 75-7875 mm (Type 90) Field Guns • 78-8047 mm Ant i-Tank Guns 8I-8537 mm Anti-Tank Guns 86
Open Artillery Emplacements 87-8847 mm Anti-Tank Guns 8737 am Anti-Tank Guns 88
Mortars 89-95320 mm Spigot Mortars . 89150 mm Mortars 90-9281 mm Mortars 93-94Grenade Launchers . 95
Rockets 96-IOO200 mm Rocket Launcher 96-98250 kg Rocket Launcher 9963 kg Rocket Launcher 100
Pillboxes 101-103Rifle Pits 104-105Tanks 106-108Dummies 109-111Radar and Radio Station 112Revetted Vehicles 113Air Raid Shelters . . . . . . . 114-115Ammunition Storage '. 116-117Miscellaneous ... . . . . 118-119
MAP APPENDIXEnemy Defense Installations as observed from ground study.Arcs of Fire for Casemated Coastal Defense Guns on Iwo Jima.Anti-Aircraft Defenses.Blockhouses with principal directions of fire indicated.Covered Artillery with principal directions of fire indicated.
Japanese Defensive Plan At Iwo JimaThe strategic importance of IWO JIMA. need hardly be emphasized. Its value as
an airbase midway between the MARIANAS and the heart of JAPAN has already beenproved. After the occupation of SAIPAN, the Japs must have known that IWO would beattacked* The only question was VHEH. The story of their haste in constructingdefenses is told in aerial photographs from 15 June 1944 until D-Day, 19 February1945.
INCREASE OF FORTIFICATIONS
At the time SAIPAN was invaded, only AA defenses, hasty fire trenches, and preliminary beach defenses had been prepared at IWO JIMA, By September 1944* positionshad been constructed in depth behind the beaches. Company and platoon positionswere then in evidence, and concrete pillboxes and covered artillery emplacementswere under construction. By December, most beach positions were completed and hadbeen strengthened by the construction of heavy concrete blockhouses. A cross-islanddefense line in depth protecting the northern part of the island was springing upalong the high ground north of Airfield No. 1. Additional AA defenses, increasednumbers of covered artillery and coast defense guns, and more and more concretepositions and minefields on the beaches were noted on each succeeding photographiosoftie. By D-Day, key positions had been connected with pillboxes and were protectedby covering fire from artillery, anti-tank guns, and mortars, previously sighted in.
Intelligence prior to the invasion of IWO indicated a formidable garrison forcewith many major caliber weapons and extensive tank and personnel obstacles; however,aerial photographs and maps gave only a limited picture of one of the enemy*s bestdefensive weapons, the terrain. An amphibious assault in force was limited to theeast and west beaches of the narrow southern part of the island. These conditionsgave the Japs an advantage in preparing defensive positions for all-around security.Only small groups were needed to cover very narrow beaches with steep exits alongthe northern coast.
COVER AND DISPERSAL
, Captured documents, confirmed by ground study, indicate the enemy's battlestrength was conserved by countermeasures against shelling and bombing. The terrainwas well suited for cover, and caves were so numerous in some sections of the islandthat it was impossible to plot them all on a 1:10,000 map. The coarse, loose, volcanic ash kept damage from shell fragmentation to a minimum. Ammunition, stores,and personnel were dispersed in caves and behind protective terrain where navalgunfire and artillery could not reach them.
CAMOUFLAGE
Camouflage encountered and camouflage discipline during construction, as evaluated from aerial photographs, was excellent. Positions were at all times coveredwith materials which blended into the surrounding terrain and vegetation. Spoilfrom excavations was planted with grass to obliterate traces of military activity.Natural vegetation was used to a large extent to conceal well-built positions fromaerial attack. While such practices could not always elude photographic interpretation, nevertheless many positions were not detected until gun fire had blown awaythe concealing vegetation. Maximum use was made of IW0*s sparse growth for concealing trenches, rifle pits, machine gun and artillery emplacements. Positions aslarge as those housing 120 mm Howitzers were undetected under the protective coveringof trees in their natural state.
COAST DEFENSE
Coast defense artillery ranging from 4.7" (120 mm) to 6M (I55 mm) guns wasinitially effective against our ships. All CD guns were casemated in four to sixfeet of reinforced concrete. Each emplacement was so positioned in the terrain that
it was normally protected from naval gunfire. A ship taking a CD gun under directfire necessarily exposed itself to the gun at which it was firing. Many guns wereso camouflaged that their location was unknown, until they opened fire.
ANTIAIRCRAFT
Antiaircraft batteries were numerous, including 120 mm DP, 100 mm, 75 mm, and25 mm in triple, twin, and single mounts. The Japs could not satisfactorily concealthese weapons, but their continued use against aircraft and our personnel ashoretestifies to the sound construction of their emplacements.
EAST BEACH POSITION
The elaborate trench system facing the eastern beaches had been entirelyabandoned. The loose nature of the sand suggests their presence as dummies, although they may have been prepared originally as hasty beach defenses before adequateconcrete positions were built. Well-constructed blockhouses encasing 25 mm machinecannons to 120 mm short naval guns were the first defenses encountered on and nearthe beach. Some concrete pillboxes and sandstone revetted rifle pits gave infantryprotection to the heavier weapons. The ground at the base of Airfield No. 1 wasmore suitable for dug in positions, and most of the infantry positions protectingthe east beach were here. The positions were not so much the target for naval gunfire, and excellent observation and good fields of fire were afforded here. Theposition of Airfield No. 1 limited the depth of these positions to approximately500 to 700 yards. Supporting fires were delivered from the flanks using the observation provided by Mt. SUHIBACHI and the high ground over the East Boat Basinand around Airfield No. 2. The area between the beach and Airfield No. 1 was steepand impossible for wheeled vehicles* to traverse. Movement of infantrymen and tankswas impeded by the loose soil with the result that they offered excellent targetsto anti-tank and anti-personnel guns and tactics.
WEST BEACH POSITIONS.
The defenses of the West Beaches were probably more extensive and elaboratethan East Beach defenses.' Airfield No. 1 permitted these defenses to be 700 to 1400yards deep giving considerably longer fields of fire and permitting a more elaboratesystem of dummy positions fronting the actual main positions and designed to drawour preliminary bombardment. The terrain was much more substantial for caves andunderground shelters, and positions were better protected from our naval gunfire.
SURIBACHI POSITIONS
In the south a cross-island defense line was constructed on the terraced slopeswhich guarded the approaches to Mt. SURIBACHI. It consisted of a maze of concretepillboxes, bunkers, shelters, and blockhouses which were capable of all-around defense and were mutually supporting. In addition to this elaborate surface organization, there was an equally elaborate subsurface organization of shelter, passageway, living quarters, storage areas, and cave-type firing positions which providedadequate protection against the heaviest of bombs and shells. The excellent observation from the heights of SURIBACHI and the high ground around Airfield No. 2were the feey to controlled artillery and mortar fire,
MAIN DEFENSE BELT
Since landings in strength were limited to the east and west beaches near thesouthern end of the island, the enemy prepared his main defense in depth in a cross-island belt. Beginning in the west at the rocky cliffs to the north of the westernbeaches, it stretched east across the island to skirt the southern end of AirfieldNo. 2, and terminated in the cliffs which form at the northern end of the easternbeaches. The center of this belt was 2600 yards deep. It gained its strength fromits depth and its concrete and steel structures, positioned so as to obtain longfields of fire which were carefully calculated and tied into the overall defensesystem. Reliance on caves as a shelter and a fighting position was increas'ed here.
Most of the positions showed excellent engineering and terrain appreciation. Communications were maintained by trenched wire, radios, and a labyrinth of undergroundtunnels connecting all areas. One of these tunnels was explored for 800 yards,and 14 entrances were found; it housed two battalion command posts and was equippedwith lights and telephones. Artillery, including heavy mortars and rockets in andbehind this defense belt, could cover most of the beach area. Positions were provided with complete preregistration data.
Strong points were established around commanding ground, Conorete-faced cavesand infantry positions in the erosion-made crevices were frequently so close together that an equally strong defensive position existed only a few yards to therear or flank. Contact became so close that safety of our own troops prevented useof artillery, naval gunfire, or air support in reducing these positions. One bluff,forming something similar to an amphitheatre, contained two terraces and three tiersof concrete pillboxes and oaves*
FINAL DEFENSIVE AREA ' • •
North of this cross-island defensive sector, the extremely rough terrain fromthe coast to 2000 yards inland created a natural defensive area. The number ofcaves and terrain characteristics somewhat compensated for the reduced amounts ofconcrete and steel. These features, coupled with the masses of men employed, tendedto make this final defensive area equally as strong as the main defensive positions.In attacking these positions no Japs were to be seen, all being in caves or crevicesin the rocks and so dispersed as to give an all-around interlocking defense to eachsmall compartment. Attacking troops frequently were subjected to fire from flanksand rear more than from their front. It was always very difficult and frequentlyimpossible to locate exactly where defensive fires originated.
In defending IW0 JIMA, the Japs employed one basic tactic which in a sense wasa departure from the Japanese defensive operations hitherto generally encountered.This tactic was simply to occupy previously determined D-Day positions and maintainthem, without recourse either to costly rtmain effort" counterattacks or organizedwithdrawals. This plan was not only simple in conception but in general was skillfully executed and well adapted to the terrain of IW0 JIMA. There were no organizedattempts made to counterattack our beachhead, no large scale night counterattacks,no "all-out" banzai charge. Instead, the enemy committed a minimum number of troopsto the southern beach area and defended it by delivering heavy volumes of fire fromboth SUHIBACHI and the north so that even when the southern area was finally taken,the bulk of the enemy's forces remained intact and were well entrenched in the mostheavily fortified part of the island. The enemy, by continuing to follow his simplebut basic defensive tactic of occupying a position and refusing to yield until dugout and killed without counterattacking and without withdrawing, was able to maintain organized resistance for over twenty days. There were no tactical withdrawals,no retrograde or delaying actions in the military sense, though in some instancesisolated withdrawals were made to preserve units and individuals threatened withinevitable destruction. It is now known that this defense of holding to the endwithout counterattack or withdrawal was the express plan conceived by the CommandingGeneral. It was this simple tactic, coupled with the incredible rocky terrain andthe maximum use the enemy had made of this terrain in constructing fortified positions which made the capture of IW0 JIMA so difficult*
ANTI-TANK TACTICS
Captured battle plans indicate the enemy's fear of our tanks. Mine fields,magnetic mines, and explosives carried by hand were employed at the beach where theloose sand seriously impeded the movement of even full-tracked vehicles. Anti-tankguns, mainly the high velocity 75 mm and 47 mm, were the principal weapons employedinland. Many anti-tank guns had one or more supplementary or alternate positions*These weapons were sited in terrain affording fields of fire covering possible tankroutes from the beach; however, considerable emphasis appears to have been placed onlocating an emplacement where it was protected by an abutting bluff or terrace, whichshielded it from frontal flat trajectory fire.
BLOCKHOUSES AND PILLBOXES
Blockhouses and pillboxes near the beaches on the more open terrain were almostinvariably sited for flanking fire. Wherever possible, a pillbox was behind a naturalmound of sand. It often had only a small fire port which allowed approximately 30°of traverse; however, there was a sufficient number of mutually supporting pillboxesto offset the restricted field of fire of each weapon.
Many blockhouses near the beach had sand piled as high as 50 feet in front ofthem. A narrow fire lane through the sand revealed the direction of fire, but manypositions were so well protected that they were still firing until reduced by infantry. Pillboxes were protected similarly; infantry commanders often found itnecessary to request main battery fire from naval vessels when secondary batteryfire could not blast the sand from in front of well built positions.
OF TANKS
Relatively few tanks, medium and light, were present on IWO JIMA. The roughterrain, size of the island, and fixed nature of defenses probably account for thelimited number. Their manner of employment was as an anti-tank weapon. They wereused in support of the main cross-island defense belt either in a revetment or behind protective terrain, camouflaged and stationary. Their 37 mm, 47 mm, and 57 mmguns fired anti-tank and personnel missions like the many 47 mm guns. Reports indicate small tank units were to be employed to support local counterattacks. Thereis little evidence they were so used. The torn up condition of roads and constantartillery fire may well have prevented any movement.
ARTILLERY
Artillery tactics were characterized by good observation and careful preplanningof fires. Range stakes were found in the vicinity of landing beaches. The elaboratecasemated structures in which artillery pieces were housed, the cave positions fromwhich mortars and rockets were fired, operated to limit the number of pieces whichcould be brought to bear on a single area. Despite perfect observation, artillery,rocket, and mortar fires were never massed against us in the same manner in whichwe mass artillery fires. Dual purpose guns were used to fire time fire over ourtroops*
An artillery group gave coordination to all field artillery and mortar employment; coast defense and AA artillery were not included in this command. Mortarshad the primary mission of filling in the gaps between the fires of the other guns,but after the land fighting stage was reached they shifted to control of sectorinfantry commanders.
The principal locations of mobile artillery were in the higher ground north ofAirfield No. 2 with forward OPs in prominent elevations along the main defensivebelt. There definitely were more weapons at the disposal of commanders than wereorganically assigned to the units. The fixed nature of the defenses permittedpersonnel normally used for ammunition carriers and for the movement of mobileweapons to be employed to man additional weapons added to basic tables of organization.
MORTARS AND ROCKETS
Although approximately twelve 320 mm spigot mortars were encountered on theisland, their effectiveness is doubtful. Emplacements were well constructed andconcealed but only a few rounds were fired. IWO's terrain was suited for the useof the many 150 mm, 81 mm and smaller mortars found there. Ammunition was storedthroughout the northern half of the island in caves and hasty firing positionswere utilized at the entrances. The 150 mm mortars were used to fire on landingbeaches. These weapons and the smaller mortars were withdrawn as the situationdemanded.
Three types of rockets were used as artillery weapons. Several positions weresighted for firing at ships approaching close to shore. The V-trough launcher wasused for 63 kg and 250 kg aerial bombs with rocket motors providing the propellingforce. A 200 mm rocket was used from a mobile-type launcher and a launcher which ismounted on a mortar-type bipod. Rockets were dispersed in deep draws over the northern portion of the island and the launchers could be moved to the site of the ammunition.
* * * * * * * * *
It is evident that little was left undone by the Japs in constructing as formidable ground defenses as possible on an island with the size and particular terrainof IWO JIMA. A study of Japanese defense installations encountered in the field ispresented with photographs and drawings on the following pages.
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B C D E A B C MAP APPENDIX
CINCPAC-CINCPOA BULLETIN NO. 136-45
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IWO JIMA ENEMY DEFENSE INSTALLATIONS
AS OBSERVED FROM GROUND STUDY
19 FEBRUARY —19 MARCH 1945
THE SPECIAL GRID SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLE COLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.
THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THIS MAP IN SALMON WITH BLUE LETTERS AND NUMBERS. THIS SYSTEM IS TO BE USED FOR AREA DESIGNATIONS.
THE NUMBERING OF THE IOOO-YARD TARGET AREAS AND LETTERING OF THE EOO-YARD TARGET SQUARES HAS NO RELATION TO THE NUMBERING USED IN THE GRID SYSTEM.
V W X PIN-POINT DESIGNATION OF RJ106 IS BC 750-709 RJI0 6 IS IN TARGET SQUARE 132 A
CASEMATE OR BLOCKHOUSE COAST DEFENSE EMPLACEMENT, UNOCCUPIED A A HEAVY FIRE CONTROL CENTER A A AUTOMATIC FIRE CONTROL VISUAL MACHINE GUN (6.5-7.7 mm) OBSERVATION POST A A TWIN MOUNT OBSERVATION TOWER A A TRIPLE MOUNT PILLBOX A A DUAL PURPOSE PERSONNEL SHELTERS-BELOW GROUND FIELD ARTILLERY-HEAVY DIRECTION FINDER FIELD ARTILLERY- LIGHT SEARCHLIGHT COVERED ARTILLERY SIGNAL TOWER ANTI TANK -MEDIUM AMMUNITION ANTI TANK -LIGHT COMMAND POST MORTAR BURIED BUILDING ROCKET PROJECTOR, SINGLE AIRCRAFT REVETMENT VEHICLE, ARMORED
THOUSANDS OF CAVES USED FOR DEFENSIVE POSITIONS, PERSONNEL , AND STORAGE HAVE
R S T NOT BEEN PLOTTED.
'20,000 W X I Y
SCALE IN YARDS
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CINCPAC-CINCPOA BULLETIN NO 136-45 LJ
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THE SPECIAL GRID SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLE COLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.
THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THIS MAP IN SALMON WITH BLUE LETTERS AND NUMBERS. THIS SYSTEM IS TO BE USED FOR AREA DESIGNATIONS.
THE NUMBERING OF THE 1000-YARD TARGET AREAS AND LETTERING OF THE EOO-YARO TARGET SQUARES HAS NO RELATION TO THE NUMBERING USED IN THE GRID SYSTEM.
PIN-POINT DESIGNATION OF RJI06 IS BC 7 5 0 - 7 0 9
RJ I0 6 IS IN TARGET SQUARE 132 A
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CINCPAC-CINCPOA BULLETIN NO 136-45 LJ
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THE SPECIAL GRID SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLE COLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.
THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THIS MAP IN SALMON WITH BLUE LETTERS AND NUMBERS. THIS SYSTEM IS TO BE
THE NUMBERING OF THE IOOO-YARD TARGET AREAS AND LETTERING OF THE 200-YARO TARGET SQUARES HAS NO RELATION TO THE NUMBERING USED IN THE GRID SYSTEM.
PIN-POINT DESIGNATION OF RJIO6 IS BC 7 5 0 - 7 0 9 RJ I0 6 IS IN TARGET SQUARE 132 A
ANTI-AIRCRAFT DEFENSES
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CINCPAC-CINCPOA BULLETIN NO. 136-45
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A B C ROCK
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WO JIMA
THE SPECIAL GRID SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLE COLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.
THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THIS MAP IN SALMON WITH BLUE LETTERS AND NUMBERS THIS SYSTEM IS TO BE USED FOR AREA DESIGNATIONS.
THE NUMBERING OF THE IOOO-YARD TARGET AREAS AND LETTERING OF THE 200-YARD TARGET SQUARES HAS NO RELATION TO THE NUMBERING USED IN THE GRID SYSTEM.
U ! V W ;X PIN-POINT DESIGNATION OF RJIO6 IS BC 7 5 0 - 7 0 9
RJ I0 6 IS IN TARGET SQUARE I32A
B C D A B C D
COVERED ARTILLERY
WITH PRINCIPAL DIRECTIONS OF FIRE INDICATED
Q R S L E G E N D
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CONFIDENTIAL MAP APPENDIX
CINCPAC-CINCPOA BULLETIN NO 136-45
ARCS OF FIRE FOR CASEMATED COASTAL DEFENSE GUNS
ON
IWO JIMA PLOTTED FROM GROUND STUDY AND CAPTURED MAP
49'
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46 '
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45 ' 45'
17' 18' 19' 141 20" 21'
JICPOA L-50608-5 5
Cleared of mines, . t theshoulders andof road is still mined Extent of field not > nown flints are. 3•"•*"'tf6 ' s//Us iv/ vc/sficM r) 6 mines removed
252 253 Single nbrn nemispnencaiarid bombs reported in Underermine mines Box,area. 3-/0-45 stick mines <f others
This area (qpproK 100 yds square w of rood) onrained 6 Herr, mortar grenodand 53 icol mines. (-5!Magnetic mints armed 27-45 See In&drt £ (H Cosi of flares. d caps / ammo
(3) Toot-measure
.̂ r ry of mined area
baHelit p. fuzes (4! BOA /nines remove c i3>Shape charge(I) STjck qrenadetz) s' Duds,
1 nest Tieiqsconrained a i (i) &UA mines and (21) Taoe- Measure // were removedape-neat vre See Insert '/f- B~- C HIRAIWA BUY uop bomb disper \al area (65 to 70)
area (-9B) bombs 250 Kg dispersei 1 in groups of S. id £0 on each side groups IS ft. opa
easur&4 ydstich. mines (I) ROW 2 /7( rn mines250 kg bombs iv ydstick !3) Rows / Hi rn /nrnes
mines «? rows removed. /orf. her we en rows 411 removed.
This field consisted of 4 ro parallel to the beach for i
The mines were 63 kg < 'ardsrick mines were lashi ur/ed near the surface .
an overage of 35' Qgarfmines in the field. This
See Insert 0'
s or mines running approxudistance of over 1000 yar
nd 250 kg bombs with no 1 d length-wise TO the bombs The aerial; bombs were place There were approximately area i j^7rd^m9a'5
I- imr
was also Clean go of t 6minat,
Z horn road bl
min&s)
ed ynK
Insert F Pattern of Anti- Tank Trench
ines 6 J (i7j Conical <fAnti-mines Scotterec
This oreo conrained 57 Co/,and 19 Hemispherical mines
field located approt red pattern not
Removedjs) loolb Sombs
>e measure mines mines
e)Tonh mines Magnetic2) $o kg bomb a
charoe arena cm 2"Terrace wen si
I raws ... to the beach on Terrace. The rows
ZSaparT, Double and si horned mines were fovn
Removed (2*) Ant, nvasioni Horned) mine
cM mines,sonnet,
a.
Horn rninee, ydstmines \yAnfi-p
Tape measure
Some irunm Mfrnp-Hind son contdbieci scrfetf-pi
Tbe\ Conicalmin?S-w 3 rowi(f'f&rrace) onk £ ro (2 terracer),' stoy$t*4di it rt beach and 25'apart ' Hoi were present for additionc mines OneDepth chargefound- (See insert f'J.3/
63'j kgbombs, \yydstic Removed (eto box mine.5
This area contained in series of 2 with connecfing. a//
/tasty mine fie 4 yds tic A f 3 removed. 3 3
JLXtll),oito mines
horn mines i row ac'ft, a/so rape-measure,
off
nsert G" 60) Kg be •nbs remoireo' 3-i-fS rows Tort ap Pattern of mines This area contain
do/ mines I claare C) Incendi ary re. voved. 3-3-45 20 ft apart.
charge p/aced /Yard shek mines road with 2 yd ttap naz ard pattern
either side of Tape -measvre mines
This area has be&n le rot* of horn found dps turned upside, down
25 stick mines base as Depth Charge used. 16 MARCH 45
D plus 25 Mine field c/eared z no data on pattern or
Removaa mines on Red deo h If 2 On MINE SITUATION MAP (19)Smqle horn mines Green Sfemovcd
Ci)2 horn oeoch mine of ((» US A'oyy gun firs (6OJ US mcrfor duds Mined area has bee neutra/jze d of IS) VS. Novy rocket- </</, f/'/ct/on qrenodes, <2) USAircraft duds Scoftcrev md/scrim natelyt a// are IWO JIMA also srr?o//er duc/s stored am me
Compiled by Corps Engineer Section from information
received from 3d ,4 th ,5 th Marine Divisions, Appro* line f fi(i every / / " on beech 2d Sep. Engr. Bn. and 2d Bomb Disposal Co.
(4) AP mines ItS . (/'/) fr mines '3) Jnp flora 11 HI Florns L 1 wmmmm•1
0 500 1000 2000 yds
CINCPAC-CINCPOA BULLETIN NO. 136-45 MAP APPENDIX
JICPOA L- 50608-56
GENERAL TERRAIN FEATURES -Beoches
Amphibious tractor stuck Inloose sand on East Beach.
Deep footprints indicateloose character of sandon beaches.
Beaches
Marston matting on EastBeach essential tovehicular movement overthe soft sand.
Bogged down Jeep withchains on East Beachsubsequently damagedby enemy fire.
8
Beaches
Wave-cut terrace on EastBeach.
Terrace on East Beach andamphibious tractor.
Beaches
Steep gradient of beach combined with looseness of sandmade movement difficult for"vehicles and troops.
View of terrace Just inlandfrom Blue Beach #2.
10
Terrain Inland
Looking west. This Is atypical area inland alongthe West Beach. (TA-163J)
Clumps of vegetation inthe central areas concealed trenches, riflepits and MG positions.
Terrain Inland
Covered artillery position housing 47 mm ATgun firing down runwayof #2 airfield. Typeof terrain in which gunemplacements were leastvulnerable to naval gunfire. (TA-183C)
Areas of this sort provided excellent cover tothe enemy in his attemptsto infiltrate our lines.
(TA-E33M)
12
Terrain Inland
Approaching Hill 362 showing the natural ruggedterrain which confrontedtroops. Since troopscould advance here onlywith great difficulty,this terrain was a decidedasset to the enemy.
(TA-216N)
Looking, west from thi:area showing sparsevegetation. (TA-216A)
13
Terrain Inland
m
Looking south showing therugged terrain approaching Mt. Suribachi.
(TA-132R)
This picture is typicalof cave-infested northern area terrain.
(TA-234D)
14
Terrain Inland
Rocky outcrops and scrubvegetation characteristicof the northern one-thirdof the island making movement of troops difficult.
Rocky terrain near northcoast provided the enemywith natural positionsfor MGs and riflemen.
15
Terrain Inland
- *
View of terrain typicalof that encountered Invicinity of Hill 382.
(TA-200Y)
Trench cut through reckleading to gun positionsnear East Boat Basin.
(TA-166D)
16
OBSTACLES AND M I N E S - Mines
Close-up of taried oildrum with the top cutopen and ready for land-mine to be emplaced.Due to the enemy's disrupted schedule causedby cur bombing prior toD day, they did not havetime to set up the minefield in conjunctionwith the oil drums.
(TA-180X)
View of West Beach showing55-gallon oil drums whichwere to be used as landmines. Electrically controlled mines were to beput into the drums to hinder our landing on thisbeach
17
Mines
250 kg bomb burled insand as land mine.These mines were fuzedwith yardstick minesPlaced on top of thebomb and secured inPlace with fine wire.Many such mines thusemployed were locatedstrategically, andwell covered with firefrom AT weapons.
(TA-165 0)
View of the West Beachshowing one-horned conical land mines. Theentire West Beach wasmined.
18
Trip Wire
Trip Wire. (TA-201S)
This was the only evidenceof trip wire or barbed wirebeing used in this area.It proved ineffective Instopping troops from landing or advancing.(TA-148H)(looking east)
Anti-Tank Ditches
View of AT trench,(TA-198H)
View of AT trench,(TA-198H)
20
CAVES
Interior view of cave.This cave had a seriesof caves leading offin different directionsand connecting withother caves In the nearvicinity. Food, ammunition and .clothingwere found In thesecaves indicating troopshad been quarteredthere. (TA-199U)
Interior view showingsteps leading out of thecave which is about fortyfeet under ground withlarge rooms throughoutfor the quartering oftroops. (TA-199U)
21
Caves
Typical entrance to extensive cave network,extending from underneath the quarry nearthe East Boat Basinwith tunnels leading asfar bs 800 yds. toMinami Village.
(TA-183W)
Entrance to cave(TA-198X)
22
Caves
Interior view of extensive cave•network underCD gun over East BoatBasin. (TA-183X)
Entrance to cave.(TA-216D)
23
Coves
One of many caves In forward slopes of hillsguarding airfield No. 2.MGs and small arms firewas received from thesepositions which providedexcellent observation ofthe entire East Beacharea. (TA-183H)
Interior view of caveshowing steps leadingdown and passagewayleading off to eitherside where troopswere quartered.
(TA-198X)
»
Caves
Interior view of entrance leading down Into cave. (TA-199UJ
Interior view of passageway In cave. (TA-132C) Entrance to two-story cave. (TA-199U)
25
COAST DEFENSE - ARTILLERY- 15 cm CD GUNS
155 mm (15 cm) CD gun show-Ing destruction caused bynaval gun fire. Reinforcedconcrete 4 ft. thick. Entrance to these casematesIs In the rear connected by-cave networks which wereused as personnel shelters,food storage and ammunitionstorage. These guns wereset about 15 yds. apart andhad a field of fire cover-Ing the entire West beachesand areas out to sea.
(TA-216D)
Ruins of 155 mm (15 cm)CD gun. (TA-216D)
26
15 cm CD GUNS
Rangefinder placed betweentwo CD guns in same areaused as part of fire control equipment.
(TA-216D)
Front view of blockhousehousing a 155 mm (15 cm)CD gun. Destructioncaused by naval gun fire,Entrance Is in rear ofblockhouse with adjoining caves throughout forpersonnel shelter, foodstorage and ammunitionstorage. (TA-216D)
27
15 cm CD GUNS
Rear view of 155 mm (15cm) CD gun In blockhouseshowing destructioncaused by naval gun fire .
(TA-216D)(SW)
Ruins of casemate containing 155 mm (15 cm) CD gun,Two such Installations,built of reinforced concrete with walls over 4ft. thick and connectedwith rangefinder and OP,were located on the edgeOf a cliff at TA-219A.
28
14 cm CD GUNS
View of cave entranceleading from casemated140 mm (14 cm) CD gunback. Into the base ofthe crater.
(TA-132L)
Breech-block view of oneof the 140 mm (14 cm)guns at the foot of Suribachl showing destruction. It is known that"these guns were silencedprior to our landing butruins of these installations provided cover forthe enemy and affordedan opportunity to inflictcasualties on troops advancing toward Mt. Suribachl. (TA-132K)
29
14 cm CD GUNS
Front view of one of the140 mm (14 cm) CD gunsshowing destructioncaused by naval gun fire
(TA-132K)
Front view of one of the140 mm (14 cm) CD gunscasemated at the foot ofMt. Suribachi. They wereconstructed of reinforcedconcrete about 4 ft.thick with tunnels leading from the rear intothe base of the mountainand connecting each installation. These tunnels also connected topersonnel shelters, foodstorage and ammunitionstorage. (TA-132K & L)
30
14 cm CD GUNS
STAIRS TO AA GUN ON ROOF
ENTRANCE TO ADJOINING ROOM
Plan view of 140 mm (14 cm) CD gun with 30-footfire port. This Is one of the four emplacementsfound at the base of Mt. Surlbachi. (TA-132 K)
31