Hiding in plane sight.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

Boise State's stadium was the first non-green football field in the world.

Jail from the 19th century that was built by inmates.

The Denny Substation has been called "the coolest substation in the world" and sits in a densely populated Seattle neighborhood.

The tech giant built three enormous glass orbs in Seattle so employees could work inside a rainforest greenhouse.

Now housed in a museum, this giant pink elephant stood in downtown Seattle for more than 60 years.

A museum dedicated to the history and exploration of both popular music and science fiction.

A community gathering place that once housed half-ton tanks and the World's Fair.

In the absence of a Chinese-language newspaper, for years the community posted daily updates on this simple bulletin board.

An old-timey peepshow allows visitors to gawk at some of the world's most freakishly large footwear.

The longest and widest floating bridge in the world.

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

A historic house in St. Louis was plagued by a series of suicides committed by family members involved in a successful brewery.

One of few surviving standpipe water towers in the U.S.

This is not your typical jungle gym.

This titanic oil company sign is a reminder of the Americana boom of the 1970s and also its commoditization.

A free, canine-friendly alternative watering hole near the more famous Barton Springs.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

Costa Rican accommodation resembles a crash site, but with a nice balcony.

Neo-cave art on the macro scale.

A colorful narrow alley in Cuba is full of street art and sculptures made of found objects.

His music once banned in Communist Cuba, John Lennon is now immortalized in bronze by Castro, who considers Lennon a "fellow dreamer."