The Wadden Sea, Germany and the Netherlands
Sandy shoals, sea grass meadows, salt marshes, dunes, and other coastal features make up the Wadden Sea (pictured in 2007), one of the world's last remaining large and intact tidal ecosystems.
(See a regional map
Named in June 2009 as a new UN World Heritage site, the sea is home to marine mammals such as harbor seals, gray seals, and the harbor porpoise
. Its coasts
provide refuge for up to 12 million birds that winter and breed there each year.
Chosen by a committee of the UN's Educational, Scientific, and Cultural Organization (UNESCO), World Heritage sites denote natural and cultural areas recognized for their universal value to humanity.
In late June officials added 13 new sites to the UNESCO list of 890 areas worthy of preservation and protection—and removed one. Dresden, Germany's Elbe Valley lost World Heritage status due to a new four-lane bridge.
(See pictures of natural wonders added to the list in 2008.
Sites added to the List of World Heritage in Danger include the the Belize Barrier Reef Reserve System, Colombia's Los Katios National Park, and the historic monuments of Mtskheta in Georgia.
Photograph courtesy Martin Stock, UNESCO