Thursday 4 December 2014

Exploring a Japanese War-time Tunnel in Hong Kong

There are a large number of war-time tunnels left in Hong Kong. Some of these are Air Raid Precautions (ARP) tunnels built before the war as part of the civil defence preparations. They remain today but the entrance portals are bricked up.

There are three portals for instance at the end of Old Queens Road as shown below. I wonder how many people realize as they walk nonchalantly by, that these were war-time air raid tunnels where hundreds of civilians took refuge from the constant bombing and shelling that occurred during the three weeks of hostilities between 8th of December when the Japanese Imperial Army crossed the border into Hong Kong and 25th December 1941 when the British Crown Colony capitulated after a short but brutal period of fighting.

People walking past air raid tunnel portals on Old Queens Road (Source: Wikipedia)
Here's another photograph showing an air raid tunnel on Queens Road Central immediately opposite HSBC's Head Office Building. The photograph was taken in 1941 only months before war erupted. The air  raid tunnel is still under construction. The stone ramparts and the steps up to Battery Path are unchanged today. Battery Path then as now leads up from Queens Road to the former French Mission building built by the Mission D' Etrangeres de Paris in 1917 and further up, the path leads to St John's Cathedral built in 1848 only six years after the First Opium War.

1941 Photo of air raid tunnel under construction (Source: University of Wisconsin-Milwaukee Libraries)

But there are other tunnels in Hong Kong often hidden in the country side. I stumbled across this one on  Monday this week. The photograph below shows the entrance.

Japanese tunnel entrance on a hillside at Smugglers Ridge (Writers Collection)
These tunnels are found all over Hong Kong and they were built by the Japanese in the closing stages of the war in anticipation of an allied invasion of Japanese occupied Hong Kong. A machine gun could be placed at the tunnel entrance, the portal would have been camouflaged with netting, sticks and leaves and would have been difficult to see until you were shot at.

This one is on a hill side at the eastern end of Smugglers Ridge near the defensive line known as the Gin Drinkers Line (GDL) named after Gin Drinkers Bay at the western end. The GDL was a line of pill boxes, barbed wire entanglements, trenches, weapons pits and minefields running east-west across the Kowloon Peninsula. The Japanese penetrated the line when they seized the Shing Mun Redoubt on the night of 9th/10th December 1941. It was the loss of the Shing Mun Redoubt and the weakness of the left flank of the GDL that necessitated the earlier than anticipated evacuation of the Mainland. Thereafter the Island of Hong Kong was besieged. Japanese troops landed on the night of 18th/19th December and moved quickly inland. Without an air force, outnumbered and outfought, the British forces surrendered  on Christmas Day after a gallant and bloody fight.

Smugglers Ridge is a narrow ridge with a path running along the top that links up Golden Hill Road with the Shing Mun Redoubt and below it  the dam and the Jubilee Reservoir. On one side of the dam is the reservoir and on the other the Shing Mun River valley. The Shing Mun River today and back in in 1941 had been reduced to a trickle after the construction of the dam around1935.

Sgt. Robert Robb and some 12 survivors of No 8 platoon that were guarding the Shing Mun Redoubt extricated along the ridge path once they realized that they were surrounded, outnumbered and that the  Redoubt had been lost. Their Company Commander Captain Cyril ("Potato") Jones and their Platoon Commander Lt Jack Thomson were caught in the Artillery Observation Post above the Redoubt and were later blown out with explosives and grenades. They survived and were amongst the first prisoners of war taken by the Japanese. Lt Thomson being blinded in one eye from shrapnel.

Shrapnel damage to the Artillery Observation Post (AOP)  at the Shing Mun Redoubt (Writers Collection)
Captain Jones bottom left, Lt Thomson with eye patch and other defenders of the Shing Mun Redoubt taken prisoner on 10th December 1941 (Source: Stills from Japanese film clip)
Anyway back to the Japanese tunnel. We would never have found this tunnel had we not gone off the path and down the steep hill side towards the Shing Mun River Valley. This is the typical way in which these tunnels are discovered - you literally stumble across them.

Stuart in the tunnel (Writers Collection)
Having found the tunnel - it needed to be explored - not something I am ever keen on because of the risk of cave-ins, the fact that they often contain bats, and I have felt their fury bodies brush my face before in other such tunnels - and I am not that keen on bats !  Another time, although I was not there, my friends were exploring a tunnel like this, when something came bounding along the tunnel. It scared the living daylights out of them and turned out to be a rather large porcupine.

So in we went - and I made sure my friend Stuart was in front. The cave turned out to be a network of interconnecting tunnels.

Bats hanging about and other creepie crawlies (Writers Collection)
It turned out there were three portals (A, C and D below) on the same side of the hill as we had entered. Two were open and one had caved-in at the entrance. Another tunnel (shown in above photograph) had a strong breeze blowing through it, the reason being we discovered was that it ran right through the ridge, under Smugglers Ridge Path and came out on the other side of Smugglers Ridge facing Golden Hill (at portal marked B in the schematic below).
With the schematic diagram below imagine folding the paper in the middle so that the upper and lower halves of the sheet of paper slope down like a tent  - this is what the terrain looks like - the fold in the middle being the Ridge Path.

Schematic of tunnels and portals  (Writers Collection)
The tunnels were fairly narrow. Every now and then a kind of alcove or shelf had been hewed out off  the wall which may have been used as a shelf for an oil lamp. We found the denigrated remains of one such lamp.

Some of these tunnels have different levels i.e. you may go up a level and reappear at a portal higher up the hillside. Many have a brick or stone parapet at the entrance behind which a machine gun could have been positioned. Some of the Japanese tunnels are quite large and include room like structures which could have served as accommodation for a number of men or storage rooms for ammunition and suppplies. In some cases the portals are large enough to hide a light tank or a field gun but most are like this one, narrow with multiple portals usually on hillsides.

Happily no porcupine came charging out - and the bats were docile just hanging around (literally) rather than flying around. The metal detector showed nothing other than the remains of the lamp. I suppose ammunition, water and rations could have been stored in these caves. If the Allies had landed and these tunnels had been used, the enemy could literally have gone to ground. The tunnels are quite long and turn corners, so a grenade thrown in may not be sufficient.  The Japanese were determined to fight a guerrilla war if the Allies landed, and as in the Pacific Islands, they were prepared to fight to the end.

Lawrence Collyer was a civilian internee at Stanley Internment Camp - in his diary he reports on the sound of blasting as the Japanese hurriedly started to construct these tunnels in the hillsides all round the Island, working day and night. These entries are from his diary (HK University Special Collections) for March 1945:

1st  March 1945 

Blasting carries on night and day.

4th March 1945

Blasting is still going on all round us, night and day continuously, they must be building a great deal of fortifications, most of which appear to be in the direction of the dams and reservoirs.

Most of the tunnels are built into rock and I think they are pretty safe but cave-ins do occur. …….so I would not recommend anybody going into these tunnels. I know I am not leading by example here, and this (below) is me coming out of the tunnel - but I was sure glad to be out ! 

Coming out of the tunnel   (Writers Collection)



  1. Hi, I recall as a teen living in Hong Kong, exploring a tunnel on Golden Hill Rd around the corner from the Smugglers Ridge Firing Range back in the early to mid 70s. We went through it with torches, looking back, extremely dangerous!! That tunnel went on for quite a way and branched out. It looked like there may have been a cave in as there were no roof supports. Walking on the terrain above the tunnel revealed a dip in the earth where I suspect the cave in had occurred. A Google Maps walk down that road now shows the hill side cement veneered along the side of the road, no evidence of tunnel now. Fascinating stuff ! Cheers John T

    1. Thanks, John, for sharing that memory. I seldom go in them now but many were blasted out of granite (but not all - some in softer rock - so can be dangerous). Never found much in any of the tunnels with metal detector. I think most were built in Q1 1945 when the Japanese garrison was expecting an Allied invasion to re-take HK. The tunnels still remain hundreds of them as a reminder of the Battle for Hong Kong. In December this year (2021) it will be the 80th anniversary of the battle.

  2. Hi
    Have you been to the Violet Hill Japanese tunnel? I would want to explore there this weekend but haven't found any directions anywhere on Gwulo. I'm talking about the tunnel that is marked on Gwulo as an AA gun tunnel. However the page on Gwulo doesn't give out directions to this tunnel. If you have been there, please do let me know.


    1. Sorry - I don't know this one. You could try Stuart Woods on FaceBook Battle of Hong Kong. Best, Philip