The first military presence on Mount Serapong was an Infantry Redoubt. Sir William Drummond Jervois, Governor of the Straits Settlements 1875-1877, recommended its construction in 1876. Sir William had been with the Department of Fortifications at the War Office in England before becoming Governor, so he was more than just a political person. He pointed out to the British Government that there was some 70,000 tons of coal in Singapore, and precious little coastal defence to protect it. In order to create the Redoubt, much of the primary jungle on Mount Serapong had to be cleared. This was done by using prisoners from India as a free work force.
There were two incarnations of the Mount Serapong Battery. The first was a two gun Mark VII 8 Inch BL Battery, and the second, replacing the 8 Inch Battery, and making use of its casemates and Magazine was a two gun Mark X 9·2 Inch BL Battery.
In 1885 Plans were drawn up to construct a two gun 8 Inch BL Gun Battery on the top of Mount Serapong. At the same time, Fort Tanjong Katong was be up gunned from its three 7 Inch RML Guns to two 8 Inch BL Guns. The 8 Inch BL Gun was not a standard British coastal artillery gun, and these four guns were to be the only 8 Inch BL land based guns in Singapore. Due to delays with fittings, it was to be 1887 before the guns were ready for service and the Serapong Battery came into service.
On 5th February 1887, the then Governor, Sir Frederick Weld, wrote in a memorandum to a secret report to the Colonial Office in London,“.....moreover Serapong fort is now strong enough to resist any but a very determined attack”.
In 1907, the Report of the Committee on Harbour Defences Abroad, headed by Gen. Sir John Fletcher Owen recommended changes to the armament on Mount Serapong and other coastal batteries in Singapore. In 1908, following his report, plans were drawn up to replace the guns on some batteries in Singapore. The Mount Serapong Battery was to be almost completely rebuilt and rearmed with two Mark X 9.2-Inch BL Guns on Mark V 15° Barbette Mountings.
Work began on the new battery, the 8 Inch BL Guns were removed and their emplacements largely destroyed. The No.1 Expense Ammunition Store was demolished to prevent interference with the field of fire of the new 9·2 Inch BL Gun. The No.2 Store was buried in sand, as was the passage which lead out of the Magazine to the 8 Inch Emplacements.
A new entrance to the Cartridge Store was made in the left-hand Casemate room and the room beside it was shortened to allow for a passageway. A large extension to the Magazine was constructed. This became the Shell Store, and Ammunition Hoists were built at each end. The Store is erroneously called a ‘tunnel’ by some people. The New Battery became operational around about September 1910.
The 9·2 Inch Battery was abandoned when Fort Connaught was up-gunned during the 1930s. The guns were removed and the concrete aprons around the emplacements was broken up and dumped where the guns had been. The whole area was then filled in. The 9·2 Inch Battery Command Post was left intact, and the Fort Connaught Battery Observation Post was built in front of it. The casemates remained intact and were used as storage.
in 1946 Mount Serapong became Keppel Fire Command. The Command controlled the two 6 Inch BL Guns at Siloso, and the three Twin 6 Pounders at Batu Berlayar, Fort Siloso and Berhala Reping. The Command was active until 1956, when coast artillery was disbanded. There was a coast artillery radar station on Serapong at the time to provide fire control for the 6 Inch Guns.
Around about 1949/1950, a concrete platform for a four gun 25 Pounder Saluting Battery was built roughly over the old No.2 Gun Emplacements. This can be seen it the photos above. I do not know when this was abandoned.
Just beyond the officer on the left of the photo, are two ventilators for the old 9·2 Inch Shell Store below.
During the 1960s, Mount Serapong once again found a military use. Two mobile radar stations were set up during the period of Confrontation with Indonesia.