As a tiny island city-state, Singapore can’t expand outwards — so it’s moving underground. The Jurong Rock Caverns, being built 150 metres underneath petrochemical hub Jurong Island, will be taller than a nine-storey building and store almost 1.5 million cubic metres of oil — the capacity of 600 Olympic swimming pools.
Source: Singapore’s man-made Jurong cavern allows it to expand | WIRED UK