A slab of sandstone covered with mysterious 1,000-year-old rock carvings from a vanished North American culture.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

Former meatpacking facility turned vertical farm and sustainable business complex.

What's left of the ruins of the 1893 Columbian Exhibition, or World's Fair, also known as the White City.

A lush green oasis in the middle of Chicago.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

This eagle-topped spire remembers the military commander who snatched up California for the United States.

An old whaling station now serves to give the public a look at the commercial whaling industry, no longer a part of Monterey's economy.

The oldest U.S. Government building in California, and it's State Historic Landmark #1.

This municipal playground was co-created by the father of one of the most playful characters ever.

The first safe in this California town had to hold all the gold.

This remarkably simple jail went over a century without an escape.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

The national park was once a plantation estate.

Washington's iconic carousel has a nice piece of Civil Rights history.

A historic ruin just 20 feet away from a busy highway onramp.

A former waterfront market is now in the center of town due to some interesting Boston engineering.