A third of the United Nations World Heritage sites valued for their geology, biodiversity or natural beauty are in danger. And 8 percent of all the sites—including Everglades National Park in Florida—are now considered to be in critical condition, according to an assessment from the International Union for Conservation of Nature.
The IUCN plays an advisory role in the UNESCO World Heritage program, which maintains a list of international sites of cultural or natural significance. Once a site is listed, it is up to the nation where it is located to maintain and preserve the site. Being listed in the program is deemed incredibly valuable for tourism, so the threat of de-listing can prompt countries to take action to better protect a site.