It attracts nearly 700,000 visitors each year. But Northern Ireland's Giant's Causeway, part of an iconic hiking route along the exposed Northern Ireland coast, is being irreparably damaged by visitors who are stuffing coins into gaps in the distinctive basalt columns.
Like tourists who left padlocks on the Pont des Arts bridge in Paris, people are copycatting others to the point where the coins are changing the face of the rocks, which are one of the most famous natural resources in Northern Ireland.
