The early data processor factory founded in Washington for the 1890 U.S. Census went on to become IBM.

Art deco landmark on the outskirts of Washington, D.C.

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

Press 1 for knock-knock jokes.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

Coins and medals straight from the mint await visitors to this shop in the nation's capital.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

A famous hotel houses an impression collection of mini dioramas and giant doll houses.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

This small hilltop church weaves the urban history of Washington, D.C. with the national history of the United States.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

A stone monument acknowledging Scotland's right to have a separate Parliament from the one in Westminster.

This art shopping center still boasts pieces of its past as a textile factory.

This colossal ancient jaguar sculpture was used as a vessel for the hearts torn from sacrificial victims.

In Coyoacán, a pair of coyotes crown a public fountain in reference to the ancient Aztec name of the borough.

These spectacular, symbolic serpents lie within the shadow of the Great Temple.

The striking jade death mask of an ancient Maya king is displayed in a replica tomb in Mexico City.

This colossal ancient sculpture of the monstrous Aztec rain god has a literally stormy history.

The only castle in North America to ever house European sovereigns.

Mexico City's largest market contains a Willy Wonka-esque wonderland.

These haunting ruins of a 700-year-old Prehispanic city have witnessed centuries of wars and massacres.

A disquieting Aztec sculpture displays hundreds of stone skulls representing the victims of human sacrifice.

Frida Kahlo's childhood home, now a museum of her life and works.

Remnants of the 16th-century defensive wall still stand unassumingly within Edinburgh.