“Plan for a tunnel under Lion Rock”, ran the headline in the South China Morning Post on March 15, 1961. “The motor tunnel to be driven through the Kowloon hills, connecting Shatin and Kowloon Tong, will be about a mile long.”

The tunnel project was linked to the Plover Cove reservoir scheme, with water from the eastern New Territories to be filtered at Sha Tin and pumped “through the Kowloon hills, making use of the tunnel, to service reservoirs in the north of the Kowloon Foothills-road.”

On March 22, 1962, the Post reported: “Engineers and workmen, equipped with modern machinery and explosives have dug 120 feet deep into Lion Rock Hill.”

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Work had begun the previous December. Engineers blasting through granite were using “Jumbo” – a type of machine also being used to drill the 11km Mont Blanc Tunnel, between France and Italy. “The machine […] carries five compressed air drills [that] puncture 120 holes in the rocks […] Workmen fill the holes with explosives to be set off electrically.”

By November 20, 1963, workmen had blasted 4,089 feet from the Kowloon Tong side. Another team had dug 584 feet from the Sha Tin side. With 12 feet separating the tunnels, engineer J. Payne told the Post: “We are dead on. The centres of these two sections are less than half an inch off.”