This giant temperature attraction created some giant electric bills.

Symbolic attempt to overcome the issues of life.

Part of a worldwide art project, this mysterious semicircle of concrete shapes holds the pieces of a larger story.

This open air cathedral invites all faiths to worship under the only roof big enough to fit them all: the sky.

River pirates, murderous bandits, and serial killers used this Illinois cave as their debauched hideout.

The farm where one of America's greatest leaders was raised is now a well-appointed landmark.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

This private residence was the template for one of the most beloved television homes of all time.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Only known mainland rookery of the threatened Stellar sea lion.

This historic Victorian hotel has a scandalous history of affairs and murder.

This lighthouse and shipwreck museum keep a torch burning for the memory of the SS Edmund Fitzgerald.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

Hell on Earth is actually a small town in Michigan where anyone can be mayor for a day.

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.

A 30-year-old Sycamore tree grown from a seed taken to the moon and back.

If astronomy had a ghost, it would look like this observatory.

A stunning, abandoned limestone quarry in southern Indiana provided the stone to erect the Empire State Building.

This mysterious hill seems to pull objects uphill.

Known as the "Cross At The Crossroads," this massive metal cross is just short enough to avoid the FAA.