This Florida sinkhole hides a rainforest-like micro-environment in its depths.

A haunted hill that supposedly defied gravity.

Welcome to old Florida, where a 1940s mermaid show is still enchanting visitors.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.

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

Holding the most bodies of any cemetery in the United States.

A Yiddish theater turned movie house turned rock and roll landmark turned gay disco turned bank.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Elevated freight railway turned wildly successful urban park.

The trials and tribulations of marking Poe's grave.

Rediscovered after a century, the father of the American Navy was reinterred in something dredged up from Davy Jones' Locker.

A former major munitions plant that has been converted into a sprawling art space.

The controversial urban planner who designed Washington, D.C., was buried in Maryland, and can presently be found in Virginia.

The romance of early commercial flight still fills this Art Deco destination.

At 207 feet, one of the world's longest continuous escalators.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

This statue of the "father of television" stands prominently in the United States Capitol.

Look closely and you’ll notice that the color changes a third of the way up the tower.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

An overlooked memorial honoring the local Washington residents who died in World War I.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

Home to a vast and influential collection of Shakespeareana.

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

A historic arena where the Beatles played their first concert in the U.S.