Pillboxes and Lyon Lights around the coast of Hong Kong island
The following post is courtesy of Rob Weir. He describes the pillboxes the British built around Hong Kong's coastline in the lead-up to the Japanese invasion. Over to Rob:
Pillboxes around the coast of Hong Kong island
Pillboxes (PB’s) were built on all beaches around HK Island considered suitable as landing sites for water borne attackers, as well as the waterfront areas along the northern coast in built-up areas .
[Each red marker shows one pillbox. Click any marker to see its name. Click the name for more details, and to see if we have any photos of that pillbox.
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The map shows an obvious exception to the waterfront location: PB 45, built overlooking the valley behind Quarry Bay.
Originally, 72 pillboxes were planned, but as a result of exercises this was increased by at least a further six, and a photo exists of another one previously unknown .
Built to house the Vickers machine gun, they were considered bullet- and splinter-proof. Walls and roof were 12 inches (30.5 cm) thick, reinforced concrete. Each pillbox had between two and four firing loopholes, covered with outward-opening steel doors. Soldiers entered via an outward-opening, lockable steel door.
Pillbox 30 at Turtle Cove, viewed from the sea side. We can see two firing loopholes with their steel doors, and the round Commander's Turret on top.
Close-up of a loophole and its outward-opening steel doors on Pillbox 29.
A Commander’s Turret protruded from the roof, accessed by a steel ladder inside the PB. This allowed him external visibility through an open slot, which could be closed by a sliding steel shutter. Ventilation within the PB was through a vertical airshaft on the outside rear wall and external airducts on the roof, to preformed holes through the roof. Construction of a two loophole PB was costed at £260.
The view of the Commander's Turret of Pillbox 22 from below.
The remains of the sliding steel shutter in
the Commander's Turret of Pillbox 17.
A PB crew consisted of a commander and six men for a two-gun PB, increasing by two per additional gun fitted. Fold-away canvas stretchers were used during rest periods. Two of the PB crew were designated to operate the associated, adjacent, Lyon Light (LL). This was controlled by the PB Commander through voice via a speaking tube connecting the PB and LL, or predetemined whistle signals.
Remains of a couple of the fold-away stretchers on the walls of Pillbox 21.
Construction of these PB’s did not commence until after the revised Defence Plan of 1938 aimed to fully defend HK Island only. Initially, only those on the West, South and East coasts were constructed, due to difficulty in obtaining suitable land in the built-up area along the North coast.
As the probability of war increased in 1941, PB’s were built in the missing areas, but these were of a slightly different design, characterised by individual air vents on the roof, and vertical “steps” in the sides of the loopholes. These “steps” were a result of experience gained in the war in Europe, where it was found that smooth sided loopholes, as previously used in HK designs, deflected bullets and shrapnel into the loophole openings.
Attempts were made to camouflage the PB’s on beaches, using stones and rocks attached to the exterior faces, and at least one is known to have been painted to resemble adjacent beach huts. PB’s and LL’s were surrounded by fences and barbed wire entanglements.
PB crews were considered expendable. "INSTRUCTIONS FOR CLOSE DEFENCE OF BEACHES HONG KONG" states, in part:
There will be no withdrawing from M.G. Pillbox. By remaining in action even if completely surrounded a delay will be imposed on the enemy during which it may be possible to launch a counter attack and drive them back into the sea.
The Lyon Light was a small (20" diameter) carbon light projector (searchlight) used to illuminate the area of water in front of the defences. The light had a maximum range of 1,000 yards under favourable atmospheric conditions, reducing in poor conditions, for example, mist. It had its own self-contained generating set, powered by a Briggs and Stratton petrol engine, producing 12V power for the light.
The lights formed an important part of the beach defence. They generally had their own small concrete shelter, positioned to the side and behind the PB, so as not to blind the PB crew. A path connecting the two often had a protective wall on the sea side. (This can still be seen at PB/LL 30).
The shelter contained the light, mounted on a concrete shelf, behind steel shutters which opened out and down when the light was being used. The engine was mounted on other concrete shelves at the back, with holes through the wall for its air intake and exhaust, and there were two stretcher beds which folded up against the wall. An airshaft and duct on the roof formed a ventilation system through an outlet above the light. Construction cost of a concrete shelter was £60.
Lyon Light 16 can be seen on along the coastal path between
Deep Water Bay and Repulse Bay.
The view inside Lyon Light 4, showing the steel shutters that would fold out and down when the light was in use.
The LL was manned by two personnel from the PB crew. Communication between the PB and LL Shelter was by a speaking tube connecting the two. Colour coded arcs were painted around the shutter opening, corresponding with the same colours in front of the PB loopholes. This ensured that, through a series of whistle blasts initiated by the PB Commander, the light would be pointing in the same direction as the guns.
In some flat areas it was not possible to get the light to a higher position, other than by building the shelter on top of the Pillbox. There are several known positions where this was done, and probably others, but the only remaining example is PB 33a. Along the built-up area of Central, space precluded the construction of separate shelters, and lights were installed in adjacent buildings.
Several LL Shelters have been identified on post war aerial photographs on the mainland, but no sites or remains have been found. No written records appear to exist.
The lights were considered such an important part of beach defence at night that written instructions at the time bore the ominous note that, once the light had been exposed (illuminated), it should remain illuminated until the landing was defeated or the light was destroyed.
Beach Defence Units
The "Infantry Beach Defence Unit" was the official title of the combination of a Beach Pillbox, and its associated Lyon Light.
Depending on the length of the beach, there may be more than one unit (e.g. Repulse Bay beach had three, 17,18 and 19). Each unit was surrounded by barbed wire.
- The reference for the PB positions is the HK Interim Defence Plan. A copy can be viewed at the UK National Archive, their reference WO 106/2379.
It was produced after the 1938 decision to attempt to defend only HK Island. It has some hand-written amendments dating up to Nov 1941, so presumably it was sort of current. It doesn't, however, have any details of Mainland defence using the extra forces created by the Canadians, and also misses out on positions of 'fill-in' PB's e.g. 51a.
- Pillbox ???: http://gwulo.com/node/2110
- Because the LL and PB were so close, in many cases the same coordinates have been used for both.
- This is best information available I have at present (2014). Further information or corrections will be appreciated.
Thanks to Rob for sharing the results of many hours of research and field trips. If you can add any photos or information about Hong Kong's pillboxes, please get in touch.
Elsewhere on Gwulo.com this week: