The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

It may appear to be a fancy junk yard, but each item has a story to tell and a lesson to impart.

This secluded walking trail is a hidden gem of a Pittsburgh park.

A quiet, gothic haven nestled between Pittsburgh's Squirrel Hill and Point Breeze neighborhoods.

Bar full of oddities, specimens, artifacts and homages to the great dime museums of the past.

A surprising, but overlooked example of geology in the middle of the nation’s capital.

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

This lovely pocket park is one of the most under appreciated in D.C.

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.

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

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

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

The towering figures were created from the cemetery's fallen old-growth trees.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

The span is crooked and made from two older recycled bridges.

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

A celebrity from the late Cretaceous period.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

There's a crumbling old mansion inside the Smithsonian National Zoo.

An Industrial Revolution-era public work that purified water using nothing but sand.

People escaping slavery may have hidden inside a corpse vault.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.