Both nations claim Santa Rosa de Yavarí, a tiny island of just 3,000 people that sits in the Amazon River, more than a thousand miles from their capitals.

Peru maintains it owns Santa Rosa Island based on treaties about a century old, but Colombia disputes that ownership because the island had not yet emerged from the river at the time.

The island of Santa Rosa sits in the Amazon River between Colombia and Peru, with Lima recently naming it a district.

The island is made up mostly of forest, farmland and a small village known as Santa Rosa de Yavari, which has a population of less than 1,000 people, according to Peru’s latest census.

The island is made up mostly of forest, farmland and a small village known as Santa Rosa de Yavari, which has a population of less than 1,000 people, according to Peru’s latest census.

The island is made up mostly of forest, farmland and a small village known as Santa Rosa de Yavari, which has a population of less than 1,000 people, according to Peru’s latest census.

Santa Rosa was previously classified as a community within the Yavari District of Peru’s Loreto Province. In June, Peru’s congress voted to turn Santa Rosa into its own district, a move that could ...