Cát Bà Island is the largest of the 367 islands that comprise the Cát Bà Archipelago, which makes up the southeastern edge of Lan Hạ Bay in Northern Vietnam. The island was largely influenced by both the First Indochina War (1946-1954) and the Second Indochina War (1955-1975), when local residents were continually forced to hide among the island’s many caves. Hospital Cave was a secret, bomb-proof hospital during the American War and as a safe house for Việt Cộng leaders. In 1979, after the Third Indochina War (1979) and the collapse of Vietnam-China relations, the Vietnamese government evicted approximately 30,000 ethnic Chinese fishermen Hạ Long area.