Long Sơn Island is an island

Island

An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...

 off the coast of Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

 near Vũng Tàu

Vung Tàu

Vũng Tàu is a city in southern Vietnam. Its population in 2005 was 240,000. The city area is including 13 urban wards and one village. It is the capital of Ba Ria-Vung Tau province, and is the crude oil extraction center of Vietnam. It is also known as one of the most beautiful cities of tourism...

.

The Nha Lon Long Son, the home of Ong Tran religion, is situated on the island.

During the Vietnam War

Vietnam War

The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

, the Viet Cong (C41 Company Chau Duc District Company) used the island as a rest and training centre. In November 1966, Operations Yass and Hayman were undertaken by 3rd Squadron SAS

Australian Special Air Service Regiment

The Special Air Service Regiment, officially abbreviated SASR but commonly known as the SAS, is a special forces unit of the Australian Army...

 and the 5th Battalion, Royal Australian Regiment upon the island.