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National Park Service celebrates 100 years

The U.S. National Park Service is celebrating 100 years at the tavern of the Chesapeake and Ohio Canal National Historic Park in Potomac, Maryland. They sang Happy Birthday and had lots of kids and a big cake.

Meanwhile, about 15 miles south between the Washington Monument and World War II Memorial, 1,000 people moved around with umbrellas and instructions to form the National Park Service logo out of human beings.

President Woodrow Wilson signed the service into existence Aug. 25, 1916.

Today, the national parks system includes hundreds of sites — iconic battlefields, beaches, forests, recreation areas — on more than 84 million acres in every state, the District of Columbia and in four U.S. territories. These lands hold giant sequoias, granite cliffs, more than 75,000 archaeological sites, rivers and 18,000 miles of trails, according to the Associated Press.