Students and staff from the University of Hong Kong have urged heritage status for a colonial-era boundary stone found during a field trip to Lei Yu Mun. At 172 years old, the boundary stone is the oldest ever discovered in Hong Kong.

Dr Stephen Davies, a lecturer at the University’s Department of Real Estate and Construction, identified the location of “War Department boundary stone, B.O. No.4” on an 1895 building plan for Sai Wan Redoubt in Britain’s National Archives in late September.

On October 3, during a field trip to the former barracks at Lei Yue Mun Park and Holiday Village, students and staff from the Department then found the stone at the exact location indicated on the map.

The Department has informed the Antiquities and Monuments Office of its finding, and has sent the Commissioner for Heritage a recommendation that the stone be listed as a Grade I protected object.

HKU boundary stone
(From left) HKU tutor Mr Chan Yiu-hung, lecturer Dr Stephen N.G. Davies, and tutor Mr Choi Cho-hong with the B.O. No4. boundary stone. Photo: HKU.

B.O. No4, having survived heavy Japanese bombardment in 1941 as well as extensive post-war changes to the area, is as old as Hong Kong itself.

It was positioned in Sai Wan Shan in late 1843—the same year Hong Kong officially became a Crown Colony under British law, two years after British forces first landed at Possession Point and a year from the island’s cession to London in the Treaty of Nanking.

The man responsible for laying the obelisk was Royal Engineers surveyor Major General Thomas Bernard Collinson, who would soon lend his name to Hong Kong’s easternmost point, Cape Collinson.

B.O. No4 is the only surviving reminder of Collinson’s 27 trigonometric stations used for surveying Hong Kong Island. It marked the northern boundary of military land from the abandoned Saiwan Barracks.

The words “B.O.No.4” carved on the stone stands for “Board of Ordnance”, the British military authority responsible for surveying and mapping before 1855.

Kris Cheng is a Hong Kong journalist with an interest in local politics. His work has been featured in Washington Post, Public Radio International, Hong Kong Economic Times and others. He has a BSSc in Sociology from the Chinese University of Hong Kong. Kris is HKFP's Editorial Director.