Beautiful views and Roman-style statues on the Italian coast.

An Italian geologic wonder that served as the inspiration for the landscape of Dante's hell.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.

A stunning cemetery famous for its extraordinarily delicate & lifelike mourning sculptures.

This Tuscan lake hides a 13th century town that is still visible when the water recedes.

Hundreds of hidden passageways weave through the old quarters of Lyon.

The alleged house of the Virgin Mary is tucked away in a park and nature preserve on Mt. Koressos in Turkey and is holy to both Catholics and Muslims alike.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

At 207 feet, one of the world's longest continuous escalators.

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

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.

An obscure federal monument honors the French diplomat who served as Ambassador to the U.S. during WWI.

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

Go take a picture with the inventor of the daguerreotype photographic process.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

A computer bug so primitive it was an actual insect.

A painfully obvious spy house sits right across the street from the Russian Embassy.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.