The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

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

A 19th-century architectural wonder designed by the "father of the skyscraper."

The massive machine creates cracking displays of indoor lightning.

Bouncing, delightful, mechanical art at the MIT Museum.

The statue of John Harvard isn't actually John Harvard—or even, technically, the founder of the school.

A steampunk wonderland that preserves America's history of industrial innovation.

This classic red schoolhouse is said to have been where Mary and her little lamb went to school.

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

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

An unexpected Easter egg lurks in the background of a cherub wall relief at the Breakers mansion.

A blend of art, antiquities, and Americana fill this museum, surrounded by whimsical, enchanting gardens.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

A World War II gun battery sits at the easternmost point of North America.

This splendid Versailles-inspired mansion has the largest French-style formal gardens in North America.

This local gem houses the largest collection of pre-Raphaelite paintings outside of the U.K.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

A sinister pyramid in the Frari contains the heart of the famous neoclassical sculptor.

The beautiful, fruit-covered facade hints at this building's former life.

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

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

Once the tallest building in the world and the site of “the highest dinner ever held in New York” this building now holds the most expensive penthouse in the city.

The 32nd president's sprawling cottage sits on an island enclave jointly managed by the U.S. and Canada.

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