Hidden in a small hill in Marsiling, a short distance from the old Immigration Checkpoint and the Causeway connecting Singapore and Malaysia, there lies a tunnel system that most Singaporeans don’t know about.  Accidentally discovered by the  One North Explorers not too many years ago, the mystery of what those tunnels are for, had intrigued many, and spun a host of reasons what they could be.

(above) Participants of API Spooky Tour going into the Marsiling Tunnels

Theories ranged from a connecting tunnel that goes underwater across the Causeway, to a tunnel system that leads to a nearby formerly empty mental Hospital known then as the View Road Hospital. It is now a workers’ dormitory.

This is because the British has military installations all over the place in Woodlands.

But the most compelling theory was that they were some disused British Military underground facility, abandoned after World war 2.

API pored over old maps and solved the mystery.

The red star on the map (above) showed the location of the main entrance of the Marsiling Tunnels.

The location coinicide with the location of the underground oil facility known as Woodlands North Depot, operated by the Asiatic Petroleum Company or APC.

The map below is dated 1945, and you can faintly see the words WOODLANDS NORTH DEPOT, and it leads to a jetty called the APC Jetty. You can also faintly make out the Ruthenia Oiling Jetty.

This shows that the Jetty was still in use before and after WW2.

The map below is dated 1968, and in the same location, the Woodlands North Deport was now renamed WOODLANDS SHELL DEPOT, and the jetty, WOODLANDS JETTY, which is still operated by SHELL. APC is the predecessor of Shell.

APC, through its underground Oil storage facility (Woodlands North Depot) supplied fuel oil to the British Navy, refueling the stationary Ship Oiler known as RFA RUTHENIA,  berthed at Ruthenia Oiling Jetty. The purpose of the ship Oiler was to refuel the naval vessels berthed next to it.

The Woodlands Shell Depot was disused some years later after the War and it remained in its current state till 2008.

Other countries underground fuel depot bears the same construction methods, ie., the chamfered ceiling where it meets wall…

(above photo taken from here.)

(Photo above: API Spooky Tour participants walking on disused pipes in the Marsiling Tunnels.)

(Photo above: The entrance to another underground fuel depot found in UK. The similair construction to our Marsiling Tunnel (very first photo of this article) sealed the fate of what the Marsiling Tunnels were.)

Afew months after Mas Selamat escaped from its Detention Barracks, API found that all the entrances to the Tunnels were then sealed up with bricks and plastered up to prevent anyone from hiding inside the tunnels.

Only 1 hidden entrance remained, discovered by Charles Goh, and who tied to a nearby tree, a rope to helped any explorer who wants to descend down to the Tunnels.

Additional Information, photos and other discoveries can be found at the One North Explorers website and here.

The Marsiling Tunnels has been featured in the popular Channel U series On the Beat 2 and the U’re the Man series.