Tourist Overcrowding Threatens World Heritage Sites from the Great Barrier Reef to Angkor Wat

Careless tourist behavior is eroding some of the planet's most celebrated natural and historic attractions, including coral reefs, ancient temples and UNESCO-listed cities. At the Great Barrier Reef, divers and boat anchors damage fragile coral, while at Giant's Causeway thousands of coins have corroded the basalt columns, requiring a 200-hour removal effort. Overcrowding forced the permanent closure of France's Lascaux Cave and a multi-year shutdown of Thailand's Maya Bay for reef rehabilitation.

In Machu Picchu, visitor limits were set after the site entered a UNESCO endangered list, and Angkor Wat faces wear from a viral TikTok running trend. Conservation agencies and local authorities across 98 sites are now grappling with restoration costs and stricter access controls.