Largest Roman Catholic church in North America.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

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

There’s a hidden military meme engraved on the World War II Memorial.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Home to items never before seen by the public.

The site of the climactic scene from the classic horror film is now a historic landmark.

Step into a pastel time capsule where candy is truly dandy.

Alexander Hamilton’s creation caused quite a bit of controversy.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

The fastest transatlantic ocean liner sat abandoned in a Philadelphia shipyard for decades.

A daily replay of the experiment that proved the rotation of the Earth.

This elaborate towering structure was once famed for its revolutionary height.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

Yo, Adrian!

The first American department store, and home to the largest operating musical instrument in the world.

Dr Barnes' $25 billion private collection of art and arboretum.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.