The narrowest house in America is seven feet of pure spite.

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

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

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

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

In addition to the usual gravestones, this Michigan cemetery features a birdhouse mausoleum and an Ark of the Covenant replica.

This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.

The pop art icon's gravesite is broadcast 24 hours a day on his museum's website.

Ohio's 19th-century communist micro-society.

The 25th President's marble casket can be visited in this classical Ohio tomb.

The world's largest collection of Don Quixote-inspired art.

This life-sized effigy commemorates the dedicated abolitionist and social reformer.

This lovely public park has an intriguing past and unique wooden bridges made of concrete.

It took millions of years for these rocks to resemble their mammalian counterparts.

Advice-columnist's bell tower, paid for with pennies.

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.

This memorial honors the performers who died when two trains collided.

A restored 114-year-old railroad station heralded as the most photographed depot in the United States.

The writing studio of an American adventure author, built in the style of a medieval castle.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

The commemorative stone column conceals a secret laboratory.

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

Catacombs turned marketplace.