Buka Island
Bougainville has been inhabited by humans for at least 29,000 years, according to evidence obtained from Kilu Cave on Buka Island. Until about 10,000 years ago, during the Last Glacial Maximum, there was a single island referred to as "Greater Bougainville" that spanned from the northern tip of Buka Island to the Nggela Islands north of Guadalcanal.