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

The only surviving piece of a submarine said to be the most decorated vessel in U.S. history.

City Council meetings still happen in this historic building, impeccably preserved on the inside.

A tiny plaque hidden miles into the Washington wilderness is all that remains to honor a shipwreck that left 18 people dead.

Stones speckled along Harris Avenue reveal hidden nuggets of the past.

This unique Seattle structure was designed to be the greenest commercial building on the planet.

This monument remembers the first Japanese Americans forcibly relocated during World War II.

The century-old remains of an abandoned farm town in eastern Washington.

A nearly abandoned 19th-century town on the Palouse.

Four abandoned towers hidden above the Douglas fir forest in Washington.

A beautiful footbridge with over 2,000 glass sculptures along the walls and ceiling.

An abandoned network of military bunkers and tunnels open for anyone willing to descend into the darkness.

This former mining hub holds a surprising abundance of undisturbed relics from the Old West.

In Washington's Yakima Valley lies a town "where dinosaurs roam."

A cave interior in the shape of the ancient rhinoceros, created by lava cooling around its carcass.

This dilapidated ship carcass covered in trees is a striking sight.

The site of the Wellington avalanche, one of the America's worst railroad disasters.

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

Native American burial mounds? Giant gopher dens? No one knows what created the Mima Mounds.

Local legend has it that an old, decaying staircase outside this cemetery is haunted by dozens of ghosts.

One small town in the Pacific Northwest transformed itself into a Bavarian-themed tourist destination.

Former farm staffed by mental patients is now a public park.

Hundreds of hopeful gold miners came here to get rich, but only two years later the small town was deserted.

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