July 11, 2026

Coral reef and beach in Raja Ampat, Indonesia

Imagine a city built by animals, glowing in the sunlight and bustling with life beneath the waves. That is a coral reef. Coral reefs cover less than 1% of the ocean floor, yet they support roughly 25% of all marine life. What looks like colourful rocks are actually colonies of tiny animals called coral polyps. Together, they build vast limestone structures that can last for thousands of years. Stretching about 2,300 kilometres along Australia's coast, the Great Barrier Reef is the largest living structure on Earth.

Pictured here is Raja Ampat, an Indonesian archipelago where white sand beaches meet clear turquoise waters and limestone islands. Beneath the surface, its reefs harbour more than 75% of known coral species alongside manta rays, reef sharks and countless tropical fish. Some corals glow thanks to fluorescent proteins that act like natural sunscreen, while parrotfish help create sandy beaches by grinding coral into fine sand. Together, these thriving ecosystems protect coastlines and inspire wonder worldwide.