Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A reproduction of earth's many biomes.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

Dramatic river bend surrounds a natural red-rocked pedestal.

A surreal landscape where fanged rocks rise from the ground and the ocean feels like a great mystery.

The dairy farm in upstate New York where nearly half a million people gathered for three days of peace and music in 1969.

The most confusing clock in New York.

The world's largest kaleidoscope, designed by a 1960s psychedelic artist.

Commemorating the spot where the famous scientist fed his pigeons.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

A precariously balanced rock perches on the edge of a cliff created tens of thousands of years ago by glacial erosion.

The first bridge observation tower in the U.S. offers one of the best views of Maine.

This 19th century granite fortification is one of the most well preserved forts in New England.

The world's largest rotating world.

As state high-points-by-elevation go this spot is one of the lowest, but for years it was also the hardest to climb.

Mysterious stone tower featured in many alternative histories of the New World.

Three and a half miles of cliffs, rocky beaches, Gilded Age mansions and 40 Steps to nowhere in particular.

This strange, big-tailed beast became a Pennsylvania town's unofficial mascot.

This Delaware River bridge is emblazoned with a catty slogan from a more prosperous time.

A home made entirely from scrapped, reclaimed and recycled material in Whitman County, Washington.

A town's monument to a touch-football victory 50 years in the making.

Shoreline strewn with the remains of ghostly fallen trees.

The highest point in Washington state is a volcano covered in glaciers.