This Overview captures a small segment of the Great Barrier Reef, located off the coast of Queensland, in northeastern Australia. Composed of more than 2,900 individual reefs and 900 islands, the reef system is Earth's largest structure made up of living things. The Great Barrier Reef stretches for more than 1,400 miles (2,300 km) and covers an area of roughly 130,000 square miles (344,400 sq. km).
Source imagery: DigitalGlobe