D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

The Lincoln Memorial has inspired many, even though a word on the inscription appears to be spelled incorrectly.

They sort through millions of dollars worth of diplomatic gifts on behalf of the government.

This bridge over D.C.'s Rock Creek Park is sometimes called the "Buffalo Bridge" because of its four buffalo sculptures, which were cast from a single piece of bronze.

A Spiritualist house of worship where believers communicate with the dead in the spirit world.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

This grand gothic brewery has been pumping out suds for over a hundred years.

A 10-foot-tall concrete Alley Oop statue left over from World War II now stands on the side of the road.

Why have you never heard of the second most popular tourist site in New York?

The largest Walmart Supercenter in the United States, referred to affectionately as “Mallmart,” has served the residents of Albany, New York, since 1994.

A 13,000-year-old mastodon skeleton was found during the construction of a 19th-century New York mill.

The largest roller-skating rink in the world.

The once-abandoned 140-year-old hotel used in the movie "In Dreams."

The "Skinny House" is made from scrap, salvage, and a neighbor’s kindness.

The Hudson River School comes alive at this palatial estate.

Glacial erratic or man-made dolmen? It probably wasn't druids.

At this farm in upstate New York, the former president plotted his reelection campaign.

A unique work of art that was created without permission.

From carts to cars, this leftover Roman bridge in France has managed to survive for centuries.

Explore the quarry where the marble was sourced for Michaelangelo's David.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

The yawning maw of this pagan visage is said to bite off the hands of liars.