Pai Bridge

The bridge over the River Pai is often, but erroneously, presented as built by the Imperial Japanese Army (IJA) during WW2.


Japan in Northwest Thailand during World War II

(this is a working outline, subject to major changes)

Notes for this page are located at the bottom.

    Introduction with graphical map index
                      (clicking location names on the map will lead to subordinate tables of contents).
  Northwestern Thailand general[2] history
  Chiang Mai town was attractive to the Imperial Japanese Army (IJA) for several reasons, including:
    Air access into Central Burma to support an IJA land invasion north from Rangoon
        via an established airport, the largest in northern Thailand
    An all-weather supply link via the Thai railway system
    An existing Thai military garrison
    Air facilities:
      Chiang Mai Airport
                Thai air mail service network reached northern Thailand in 1940
                Events just before the war: surveillance flights
                24 March 1942: Flying Tiger air raid
                    Bond: Leader of the attack
                    Neale: Squadron leader
                    Newkirk: killed in crash
                    McGarry: bailed out & captured
                Various aerial photos of Chiang Mai, including RAF mosaic in April 1944
                Wat Rampoeng Road: IJAAF aircraft were hidden under trees along the road
                    connecting the wat and the airfield
      Satellite airport: San Kamphaeng
    Rail facilities
                History relevant to Chiang Mai before WWII
                21 December 1943: Allied air raid on Chiang Mai railway station, 300+ killed
                    View from the air
                    View from the ground
                        Chiang Mai railway station destroyed
                        Sangthai rice mill damaged
      Transport between railroad station and airport
    Military facilities
      Pre-war: Kawila Barracks
      Thai Army actions on start of war
      IJA arrival and expansion in Chiang Mai
                Headquarters: Wattanathaipayap School
                Probable senior officer quarters
                        Queripol residence
                        Donavanik residence
                Troop concentrations
                        Nong Ho Camp
                        Wat Muen San
                        Wat Sri Supan
                        Wat Umong
                Health services
                        American Hospital: status during war, as yet unclear
                        McCormick Hospital: occupied by Thai troops at beginning of war
                        McKean Hospital: relatively uninvolved with the IJA who generally feared leprosy
                        Chiang Mai (IJA): as yet, not located
                        Don Kaeo (IJA): near Nakornping Hospital (Route 107), it is unmarked today
                        Huai Kaeo (IJA): as yet, not located
                Defense systems
                        Anti-aircraft batteries: Sources include Thai narratives & USAF aerial photos
                        Church: machine gun in steeple
                        Air raid early warning system manned by Thai military
                        Bunkers built throughout the city
    Other Japanese facilities
      Japanese consulate
      Tanaka's shop / residence
    Other points of interest
      Only power source for city: Diesel engine - electric generator located near Gymkhana Club
      Saw mill (east of Wat Phra Singh): Owned by Donavanik Family
      Saw mill (west of RR sta)
      Samranchon shop: Bicycle repair shop personnel assisted Allied POWs at Wat Muen San
      Gymkhana Club
      Schools closed:
          Prince Royal's College: closed during the war; at war's end, it became British Army HQ
          Yupparaj Wittayalai School: closed during the war; it was an anti-aircraft battery site
          Montfort College: closed during the war
          Wattanathaipayap School: closed during the war --- it became IJA HQ
          Dara Academy: closed during the war
      Coffee shop: at east end of Nawarat Bridge, Witchit Jarawan, Proprietor
      Ping River Bridges: research on the older bridges in Chiang Mai was necessary
        in order to try to determine the source of the six spans of the "Bridge on the River Pai":
               Nakhon Ping Bridge
               Foot Bridge
               Nawarat Bridge
               Iron Bridge
  Chiang Mai province, of which the town was the administrative center,
       had these additional points of interest with regard to WWII:

      0107[3] 024[3a] Mae Taeng
      0107 081[4a] Connection to Route 1178
      0107 --- 1178: 040+[4a]  Arunothai
      0107 ---          050+[4a]  Doi Pha Wok/Boundary Pillar No 16 Crossing Point
      0107 145[4a] Fang oil field
      1099 040[4a] Om Koi IJAAF aircraft wreckage
      1322 056[4a] Wiang Haeng Allied aircraft wreckage
  Mae Hong Son province: west of Chiang Mai province, with Central Burma to the west of Mae Hong Son,
       it became especially relevant during WWII because of several towns:
    Mae Hong Son town, the provincial seat
      Mae Hong Son Airstrip
      Land transportation hub
    Khun Yuam, the eventual IJA gateway from Burma
      Khun Yuam Airstrip
      Land transportation hub
    Mae Sariang, gateway to Papun, Burma
      Mae Sariang Airstrip
      Land transportation hub
    Mae Sam Laep / Tha Ta Fang, border point
    Pai, the main settlement between Mae Hong Son and Chiang Mai towns
    Muang Noi, Reported site of mass burial of IJA troops
  Route choice by IJA within Thailand to Burma for invasion of India planned for 1944

Three alternate routes were considered, and each of them played a significant role in WWII.

              1. Tak - Mae Sot (border point)
              2. Lampang - Chiang Rai - Mai Sai (border point)
              3. Chiang Mai - Mae Hong Son - Khun Yuam - Border Point 13

Each is reviewed below:
  1. Tak - Mae Sot (an existing trail into Burma and Rangoon)
      ----   --- General: 1942: most northerly IJA invasion point into Burma
    (000) 0105 000 Tak: motor vehicle road to west ends; continues as caravan trail
    (080) 0105 080±[4a] Mae Sot: road ends at Moei River on Thai-Burma border;
         across river: Myawadi, Burma, leading ultimately to Rangoon
  2. Lampang - Chiang Rai - Mai Sai Road (an existing road into Burma and Kengtung,
        with access to Mandalay, Burma, to the west and Yunnan, China, to the east)
      ----   --- General:
        1941: north-south road served as an escape route for
                 foreigners from northern Thailand
        1944: it was used to support the IJA invasion of India
                 through Burma
    (000) 0001 601±[4a] Lampang:
        HQ of IJA forces in northern Thailand
        Main transshipping point for goods coming by rail from south
                to Thai Route 1 & points north (Mae Sai & Burma)
        Airport with satellite fields at Kohga, Hang Chat, & Mae Mo
    (184) 0001 785±[4a] Chiang Rai:
        On Thai Route 1 between Lampang & Mae Sai
               with bridge over the Mae Kok River
        Airport with backup airstrip
    (245) 0001 846±[4a] Mai Sai: north end of Thai Route 1, connecting with Burma Route 4
        to Kengtung & Meiktila, 125 km south of Mandalay
  3. Chiang Mai - Mae Hong Son - Khun Yuam - Border Point 13
      (a combination of existing roads and local trails not previously used to access Burma
       and leading to Toungoo with its major north-south road, rail, and river connections)
      ----   --- General
    (000) 0107 000 Chiang Mai (travel north)
    (036) 0107 xxx Mae Malai (tee-intersection with east end of Route 1095)
    (036) 1095 000 Mae Malai  (turn west, eventually travel south)
    (251) 1095 215[4a] Mae Hong Son (junction with Route 0108b)
    (251) 0108b 265[4a] Mae Hong Son (continue south)
    (318) 0108b 198 Khun Yuam (tee-intersection with Route 3007)
    (318) 3007 000 Khun Yuam (turn, travel west)
    (334) 3007 016 Pratumuang (tee-intersection with Route 1337)
    (334) 1337 042[4a] Pratumuang (turn, travel southwest)
    (342) 1337 034[4a] Huai Ton Nun (tee-intersection with unnumbered road)
    (342) 0000[4a] 010[4a] Huai Ton Nun (turn west)
    (352) 0000 000[4a] Border Point 13 (leave Thailand: enter Burma, travel west to Toungoo)
  The IJA attempted invasion of India turned into a disastrous defeat in July 1944 with Japanese troops retreating on a massive scale. One of the destinations for those troops was Thailand. Roads documented as used to enter Thailand include:

              1. Loikaw - Daw Hse-kawle - border point - Mae Hong Son
              2. Loikaw - Daw Hse-kawle - border point - Huai Ton Nun (ホヲトン ?) - Khun Yuam
              3. Toungoo - Namman - Border Point 13 - Khun Yuam
              4. Toungoo - Mese Atet - border point - Takaun (ターカウン ?) - Mae Sariang
              5. Papun - Dagwin - border point - Tha Phang - Mae Sariang

The best organized and most heavily used was Number 3.
Each is reviewed below:

  1. Loikaw - Daw Hse-kawle - border point - Mae Hong Son
        --- General
  2. Loikaw - Daw Hse-kawle - border point - Huai Ton Nun (ホヲトン ?) - Khun Yuam
        --- General
  3. Toungoo, Burma to Thai Border Point 13 and on to Khun Yuam, Thailand
        --- General
    (000) B005
000[5] Toungoo:
        Burma Railway stop
        Transshipment point for Mawchi tungsten ore concentrate
        Crossing point on the Sittang River
        Airport built by the RAF in 1940
    (155) B005 155[5ä] Mawchi: largest tungsten ore (wolfram) mine in the world in the 1930s
    (186) B005 186[5a] Kemapyu on west bank of Salween River: Route 5 here turns north
        towards Taunggyi
    (186) Bxxx[6] 186[6a] Chiyaupeniko (? チャウペニョ[6a]) on east bank of Salween River:
        unnumbered Burmese road continues generally eastward
    (217) Bxxx 217[6a] Mesenan
    (241) Bxxx 241[6a] Mese Ale / Mese Atet
    (252) Bxxx 252[6a] Nammam
    (268) Bxxx 268[6a] Thai Border Point 13
    (268) Txxx[7] 000[7a] Thai Border Point 13
    (278) Txxx 010[7a] Huai Ton Nun (Txxx ends at intersection with Route 1337)
    (302) 1337 034[8] Huai Ton Nun (travel continues, northward, on Route 1337)
    (307) 1337 039[8] Nam Yuam Camp
    (310) 1337 042[8] Pratumuang (Route 1337 ends at intersection with Route 3007)
    (310) 3007 016[9] Pratumuang (travel continues, eastward, on Route 3007)
    (321) 3007 005 Wat To Phae
    (326) 3007 000 Khun Yuam (intersection of Route 3007 with 0108 at Sta 198)
  4. Toungoo - Mese Atet - border point - Takaun (ターカウン ?) - Mae Sariang
        --- General
  5. Papun - Dagwin - border point - Tha Phang - Mae Sariang
        --- General
  Within Thailand, from Khun Yuam, there were three major routes for IJA troops withdrawing to Chiang Mai.
     Within each of the three, locations are listed in direction of Chiang Mai
    1. Northern Route: Khun Yuam - Mae Hong Son - Pai - Mae Malai - Chiang Mai
        --- General
    (000) 0108b[10] 198 Khun Yuam
    (004) 0108b 202 Nong Ka Po
    (006) 0108b 204 IJA Road
    (014) 0108b 212 Mae Surin
    (032) 0108b 230 Huai Pong
    (060) 0108b 258 Pha Bong
    (067) 0108b 265 Mae Hong Son
    (067) 1095 215 Mae Hong Son
    (069) 1095 213+ Mae Hong Son Airport
    (069) 1095 213 Wat Chong Kham
    (082) 1095 200 Wat Phra
    (089) 1095 192 McGarry crash site
    (093) 1095 188 Huai Pha
    (114) 1095 168 Mae Suya
    (114) 1095 168-157 Forest Protection Unit 15
    (125) 1095 157 I J A road
    (144) 1095 138 Pang Mapha
    (148) 1095 134 Pha Mon
    (149) 1095 133 Mon Mai camp
    (152) 1095 130 Nam Rin
    (172) 1095 110 Soppong
    (182) 1095 100 Pai airport
    (185) 1095 097 Pai city
    (194) 1095 088 Pai bridge
    (282) 1095 000 Mae Malai
    (282) 0107 036 Mae Malai: medical facilities
    (303) 0107 015 Mae Rim
    (305) 0107 013 Wat memorial
    (309) 0107 009 Don Kaeo: medical facilities
    (318) 0107 000 Chiang Mai
    (318) 0000 000 Chiang Mai
    (320) 0000 002 Wat Muen San
      0121: Chiang Mai Outer Ring Road: paralleling Rte 107 (see Route 0107)
        000 General
        004+ Don Kaeo medical facilities (see Route 0107 Sta 009)
    Central Route: Khun Yuam - Mae Na Chon - Mae Wang - Ban Kat - San Pa Tong - Chiang Mai
      ---- --- General
    (000) 1263 000 Khun Yuam
    (068) 1263 068[4a] Mae Na Chon
    (068) 1088 xxx[4a] Mae Na Chon
    (072) 1088 xxx[4a] Turn off to east on unnumbered route
    (072) 0000 xxx[4a] Start unnumbered road to east
    (098) 0000[4a] xxx[4a] Small unnamed[4a] damsite
    (115) 0000
End easterly unnumbered road at T-intersection;
Stem of T is unnumbered road S/SE to Santi Suk on Route 108
    (115) 1013 xxx[4a] Westerly end of Route 1013 (?)
    (117) 1013 xxx[4a] Mae Win
    (129) 1013 xxx[4a] Mae Wong
    (134) 1013 009 Ban Kat
    (143) 1013 000 San Pa Tong
    (143) 0108a 143 San Pa Tong
    (153) 0108a 153 Hang Dong
    (163) 0108a 163 Beginning Route 108 (Sta 000) at intersection with Route 1141
    (163) 0000 163 Unnumbered road (Thipanet Road)
    (165) 0000 165 Wat Muen San
    Alternate Central Route: Old Elephant Trail
        --- General
    Southern Route: Khun Yuam - Mae Sariang - Hot - San Pa Tong - Chiang Mai
      ----- --- General
    (000) 0108b 198 Museum
    (000) 0108b 198 Wat Muai To
    (000) 0108b 198 Khun Yuam
    (001) 0108b 197 Khun Yuam airstrip
    (010) 0108b 188 Muang Pon
    (045) 0108b 153 Mae La Luang
    (094) 0108b 104+ Mae Sariang airport
    (094) 0108b 104 Mae Sariang
    (159) 0108b 039 Bo Luang
    (198) 0108b 000 Hot
    (198) 0108a 088 Hot
    (286) 0108a 000 Chiang Mai
    (286) 0000 000 Chiang Mai (Thipanet Road)
    (288) 0000 002 Wat Muen San
    Other routes / points of interest
      Chiang Mai - Lamphun - Pasang: Stationing may rezero at Pasang
      ---- --- General
      0106 182±[4a] Chiang Mai
      0106 131 Fujita memorial
      ---- --- General
      0011 xxx[4a]  
      ---- --- General
      0101 xxxx[4a]  
    Map Information
      Locations cross-referenced in Thai, English, & Japanese, with GPS coordinates
      Mapping terminology cross-referenced in Thai, English, & Japanese
      Thai map abbreviations
      Northern Thai airports
      Diagrams for assembling mosaics of aerial photos in Williams-Hunt Collection
      Difficulties encountered in this effort
    Summaries of translations of relevant portions of Thai language references
      Antique article
      Japanese soldiers cemetery project
      Japanese-Thai relations in Mae Hong Son
      Khun Yuam museum publications
      RTA History
      RTAF History 1913 ff
      RTAF History WW2
      Chanilpan columns
      Chiang Mai Air History
      Chiang Mai Chronicle
      Japanese-Thai Friendship in WW2
    Summaries of translations of relevant portions of Japanese language references
      Journal colecting IJA war dead
      Senshi Sosho
        vol   5:   Burma Campaigns
        vol 15: Imphal Operation
        vol 25: Collapse of the Defense of Burma
        vol 32: Defeat on the Burma Front
        vol 34:
      Chao interviews
      Wandering the Burma Front by Inoue
    Summaries of relevant portions of English language references
      IJA Unit Nicknames
      Calendar, Japanese
      Calendar, Thai
    Payap photo index



1.^ While the website name includes "Lanna", most attention is devoted to the provinces of Chiang Mai & Mae Hong Son.

2.^ In most cases, a 'General' topic includes a map.

3.^ Route numbers and kilometer stationing were not used to designate roadways during the war. The current road numbering system is here used for convenience. Numbered roads today generally follow long-established roads and trails, though subsequent highway improvements may have considerably changed road alighments.

Explanation of format:

Thai route number: Station number (eg, 0107: 024). In number pairs like this, the first number, four digits, is the Thai route / road number, and the second number, three digits, is the "station number", which is displayed on the nearest kilometer monument along the road. In many cases, the station number includes a tenth of a kilometer, which may have been determined by car odometer, or Highway Department markup on the pavement. Hence, in this case, Mae Taeng is on Thai Road Number 107 near kilometer post 24.

Thailand: this name was adopted by the Phibun government in 1939.

Burma: the country's old name is here used because it applied during this period of history. Road numbering and stationing follow the format described above with current Myanmar route designations. The method of highway stationing, if any, is unknown, and assumed for convenience. Some areas discussed are combat zones and not currently available for field verification.

3a.^ Number on kilometer post monument along Thai Route / Road (see explanation in Note 3 just above)

4. (deleted)

4a.^ Number needs field verification.

5.^ Myanmar route number was identified from maps. No information is available on highway stationing; so "000" station was arbitrarily assumed to be at Toungoo, with stationing increasing in easterly direction. Field verification is not possible.

5ä.^ Distance was taken from Crozier, S, "Memories of the Shan States", Argus Week-End Magazine. 13 Oct 1945, p 12.

5a.^ Arbitrary station numbering assigned (see Note 5 directly above)
Distances were taken from Google Earth path T-K Burma Rte 5.kml.

6.^ Maps do not show any route numbers assigned for these roads: this cannot be field verified.

6a.^ Road station numbering is arbitrarily continued from Toungoo-Kemapyu road. Distances are taken from 戦没者遺骨収集の記録 ピルマ・インド・タイ [Journal on Collection of War Dead: Burma, India, Thailand] (Tokyo: All Burma Comrades Organization, 1980), map p 427. Field verification is not possible.

7.^ Available maps do not show any numbers assigned for these roads: this should be field verified.

7a.^ Stationing for the unnumbered Thai road is arbitrarily started at "000" at Border Point 13, and increases in a generally easterly direction. This should be field verified. Distances are taken from Google Earth path K-Y.kml.

8.^ Stationing on Thai Road 1337 is assumed to begin at "000" at its intersection with Thai Road 0108b near Muang Pon, and increase in generally westerly and northerly directions. Distances are taken from Google Earth path Thai_Route_1337.kml. Stationing needs field verification.

9.^ Note that stationing in this sequence on Thai Road 3007 is real and not assumed, and the stations actually decrease because the road is stationed east to west, while actual travel traced here is in the opposite direction. Stationing needs field verification.

10.^ Thai routes 108a and 108b: Route 108 begins in Chiang Mai, with Station "000" and goes in a southerly direction with stations increasing. Near the town of Hot at Station 88, Route 108 turns west; but also starts again with Station "000". Hence there are two locations for all points on Route 108 up to Station 88. To differentiate the two, the first series is relabeled "108a" and the second series is relabeled "108b".


Revision List
2012 May 15
First published on Internet
2013 Apr 29
Toungoo-Mawchi distance revised