A relief that wraps around the concourse of Los Angeles's World Trade Center marks one of the city's failed urban design plans.

A classic American barn that was the home of a classic American television star.

"Prepare yourself! You are to become the voice of Interplanetary Parliament."

Inside this clubhouse is a cinephile's paradise.

An L.A. traffic island where the faces of locals have been carved into massive granite eggs.

The neighborhood shop is a sort of tiny cactus museum full of exotic specimens you can take home.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

This former maximum-security prison is creepy, sobering, and supposedly haunted.

This mysterious hilltop collection of Druid carvings isn't quite what it seems.

Experience the hysteria of a 17th century witch hunt through goofy reenactments and wax dummies that should probably be burned at the stake.

A portal into the bricked up canal that runs through the heart of Washington D.C.

When it comes to handsignals (and colonialism) rock always beats scissors.

Helen Keller once broke ground on this historic center for the study of technologies to benefit the hearing impaired.

Go take a picture with the inventor of the daguerreotype photographic process.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

These recently uncovered walls are all that's left of Washington, D.C's first defense contractor.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

The oldest continuously operating fish market in the United States.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

The first presidential bomb shelter was located in an old vault under the Treasury, connected to the White House via tunnel.

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

The national park was once a plantation estate.