Mesoamerican Barrier Reef

The Mesoamerican Barrier Reef is the largest coral reef system in the Western Hemisphere and the second longest barrier reef in the world, curving for more than 1,000 kilometres through the Caribbean along the coasts of Mexico, Belize, Guatemala, and Honduras. Beginning near the Yucatan Peninsula and running south past the cayes of Belize to the Bay Islands of Honduras, it shelters clear turquoise waters, vast seagrass meadows, and mangrove forests in one of the richest marine regions on Earth.

The reef includes the Belize Barrier Reef, the largest in the system, and remarkable features such as the Great Blue Hole, a near-perfect circular sinkhole over 120 metres deep that draws divers from around the world. The system supports more than 65 species of stony coral and over 500 species of fish, along with manatees, sea turtles, and the world's largest fish, the whale shark, which gathers seasonally off the coast. Its mangroves and seagrass beds serve as nurseries that sustain the whole web of Caribbean marine life.

The reef has been bound up with human life since the Maya, who fished and traded along its coasts and whose descendants still live throughout the region. Today it underpins fishing and tourism for millions of people across four countries, even as it faces bleaching, pollution, overfishing, and coastal development. Cross-border conservation efforts, including marine reserves and a regional monitoring scorecard, aim to protect a reef whose health is shared among the nations that line it.

• North America
  The third-largest continent, from the Arctic to the tropics located on
• Great Barrier Reef
  The largest living structure on Earth, a 2,300-kilometre coral system off Australia related reef