During the second world war, the whole world was in turmoil, and Hong Kong was not spared. The Kowloon Ridge was garrisoned by British and Japanese troops at different times, and later became a battlefield. To this day, the remains of the Gin Drinkers Line can still be found in the Lion Rock area.

The Gin Drinkers Line spanned a distance of around 18 kilometres. Divided into four sections: Port Shelter – One Rise More (today Tung Yeung Shan), One Rise More (today Tung Yeung Shan) – Sha Tin – Beacon Hill, Sha Tin – Golden Hill, Shing Mun Reservoir – Gin Drinkers Bay (today reclaimed as Kwai Fong and part of Kwai Hing), the Gin Drinkers Line was largely finished in 1938. When the British planners studied the defence of Hong Kong in the 1930s, they proposed to divide the operations in the New Territories into three phases, namely “Anti-landing action”, “Delay action from landing point/border to the main defence position”, and the “Final position”. The Gin Drinkers Line was the “Final position,” namely the last position for the garrison to defend Kowloon before it was withdrawn to Hong Kong Island.

The Lion Rock War Relics Trail is part of the Gin Drinkers Line. There are 16 interpretation points introducing the war ruins along the way, which comprises of pillboxes, direction slabs, trenches, military caves and blockhouse, telling the stories of war at that time. Some of them may look just like another massive rock, but they are in fact the largest military stone markers discovered in Hong Kong by now. Despite years of wind and rain, the markings on some of them are still clearly identifiable. The arrows on the direction slab actually point to the mountain trails that lead to different facilities of the line.

In addition to the military installations, there are numerous caves that were built during the Japanese occupation period and still kept in good conditions as they were originally built for possible attacks by the Allied Forces, but never came into use because the war did not take place in Hong Kong at the end. After the fall of Hong Kong, the Japanese forces inspected the pillboxes and found them too exposed. Even the camouflage helped little to conceal them. The Japanese then dug tunnels near these pillboxes to augment the defence but they were never tested in combat as the Allied forces did not try to retake the city.

After the war some of the pillboxes were occupied as dwellings or storage spaces and a number of them even became crime scenes. The British garrison and the government then decided to demolish the pillboxes along the Gin Drinkers Line, most of them now became a pile of ruins.

The remains of a British blockhouse built during the 1910s can be found at this trail. It was part of a defensive line that predated the Gin Drinkers Line for more than two decades. In 1911, Major General Charles Anderson, the General Officer Commanding Hong Kong, proposed to build a defensive line along the Kowloon Ridge that consisted of thirty blockhouses. Construction work started sometime in 1913 and the line was abandoned soon after the First World War.