The Temple of Preah Vihear

A temple on a cliff

Preah Vihear is a series of sanctuaries linked by pavements and staircases along an 800-metre axis, dedicated to Shiva and dating mostly from the first half of the 11th century, though a hermitage stood there from the 9th.^[1] It sits on a promontory of the Dângrêk range. Thailand argued that the ground gives easy access from its side, while from Cambodia it means scaling a high cliff.^[2]

The watershed and the map

Both sides agreed that the dispute began with the boundary settlements of 1904–08 between France, which then ran Cambodia’s affairs, and Siam, as Thailand was then called. The treaty of 13 February 1904 put the border in this region along the watershed, to be fixed by a mixed commission.^[2] Siam lacked the means to map the frontier and asked French officers to do it. In late 1907 four French officers finished eleven maps, printed by a French firm; one of them, the “Annex I map”, put the temple in Cambodia. Siam’s interior minister, Prince Damrong, thanked the French for the maps and asked for fifteen more copies.^[2]

Thailand said the map was wrong: the true watershed ran along the cliff edge and put the temple in Thailand. A Thai survey of 1934–35 found that divergence, but Thailand did not challenge the map with France or Cambodia until talks in 1958. In 1930 Prince Damrong had visited the temple and been received by the French resident with the French flag flying. Thailand stationed guards at the temple from 1954.^[2]

Two judgments

On 15 June 1962 the International Court of Justice found, by nine votes to three, that the temple is in territory under Cambodian sovereignty and that Thailand must withdraw its forces. Thailand, the Court said, had accepted the map by its conduct and could not now deny it, after fifty years of enjoying a stable frontier under the 1904 treaty.^[2]

The temple was added to UNESCO’s World Heritage List in 2008.^[1] Cambodia told the Court that armed clashes followed from 15 July 2008, and again in 2009 and February 2011; Thailand had written to the Security Council claiming an area “adjacent” to the temple. In July 2011 the Court ordered both sides to pull their troops out of a provisional demilitarised zone.^[4] On 11 November 2013 it ruled unanimously that the 1962 judgment had given Cambodia the whole promontory of Preah Vihear.^[3]

“the Temple of Preah Vihear is situated in territory under the sovereignty of Cambodia”^[2]

War in 2025

The dispute along the border flared into five days of fighting in July 2025, ended by a ceasefire brokered by Malaysia, then into heavy fighting again from early December.^[5] On 27 December the two defence ministers signed a ceasefire after 20 days of fighting that had killed more than 100 people and displaced more than half a million. ASEAN observers were to monitor it.^[6]