Ken Burns: Glacier National Park in trouble

If you're interested in seeing the namesake glaciers of Glacier National Park, Ken Burns has a piece of advice: hurry.

"The great sadness of Glacier National Park is that it's probably going to be true that fairly soon, we're going to call it 'The National Park Formerly Known as Glacier'," Burns says.

With current global warming trends, the United States Geological Survey warns that Glacier National Park's glaciers could disappear within the next several decades.

"If Glacier goes, we're in big, big trouble," Burns says.

The park boasts over 700 miles of trails across some of the most striking mountains, forests and lakes in the world.

But there is another awe-inspiring feature in Glacier. Watch the video above to find out what Burns calls "... One of the greatest engineering feats in the world ... a revelation, a human testament to what it is to approach and get swallowed up by nature."

As co-creator of the PBS series The National Parks: America's Best Idea, Ken Burns and his team spent months filming in national parks across the United States.

Burns sat down with USA TODAY and shared the secrets of Glacier and nine other national parks for a special 10-part series, "Secrets of the National Parks."

Check back with USA TODAY Travel weekly for new installments of "Secrets of the National Parks," featuring Ken Burns' insights into nine other parks including Yosemite, Yellowstone and more.