Magazine Island, previous explosive storage for fishermen. Abandoned after the government banished the use of fishing explosive [1887- ]
http://www.hiking.com.hk/discus/messages/2192/3274.html?1104842809
This Chinese link has some information about it's usage. It said it was built by the Government to store fishing explosives. However the site was abandoned after the banishment of such explosives. The link also mentioned there was a rumour of a British military search light post on the island.
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