Kampong Bahru is a 21m knoll situated immediately west of Sungei Mamam creek along the central northern shoreline of Pulau Ubin. During the Second World War, it was the site of a coastal artillery emplacement designed for two twin 6-pounder guns. These guns were termed AMTB equipment, and typically emplaced near the entrance of harbours in two or one gun configuration. The Pulau Ubin AMTB battery formed part of the Changi Fire Command – a network of coast artillery batteries placed to protect the eastern part of Singapore; specifically, the waterway leading into the Royal Navy base at Sembawang.
The first production batch of twin 6-pounders at the Woolwich Ordnance Factory, UK, were sent to Singapore in 1937. They armed several emplacements in Changi, Pulau Tekong, and Keppel Harbour. However, it is unclear whether the guns for Pulau Ubin arrived in time to see any action. As a result, the emplacements remain in relatively good condition as it did not suffer from direct enemy fire, and demolition by the retreating British Army. Part of the research at the Ubin AMTB was to examine whether any guns were ever emplaced at the battery.
The two gun emplacements of the AMTB were similar in layout (see figs. 1 and 2). The central gun floor area was flanked on the east side by the magazine, and on the west side by a crew shelter and artillery store. Both emplacements were built eight meters apart in a staggered formation on a terraced slope approximately mid-way on the knoll, and facing northeast. Gun no. 1 (see fig. 3) was the first emplacement from the east. Entry into the emplacement was on the west via a corridor situated between the crew shelter and artillery store. Behind each emplacement, stood a two storey (gun no.1) and three storey (gun no.2) battery observation post (BOP) tower. This structure housed equipment and men to command the guns, engines, and searchlights.
In addition to the gun emplacements, the battery also consisted of ancillary buildings such as barracks, toilets, cookhouse, engine room, oil store, storerooms, water pumping station, and searchlight emplacements. They were all built in a compact location on the knoll. A jetty located west of the gun emplacements also served the establishment. The barracks, toilets, and cookhouse have since been demolished. The engine room and oil store were located together on the south-eastern foot of the knoll, out of view from an attacking enemy ship. Both were simple rectangle concrete structures with flat roofs. Approximately 300m downhill from the northeast corner of gun no.1, and at the water’s edge, were three DEL (defence electric light) emplacements (see fig. 4). These concrete structures house fixed beam electric searchlights powerful enough to light up a section of the waterway. These would have allowed the guns to engage intruders at night or in low light conditions.
British Projects to replace the 25 Pounder field gun
Vickers Interwar Super-Long-Range Artillery