This natural French spring has been turned into a magical grotto by Roman and medieval constructions.

Send a postcard while vacationing with Satan.

An autonomous oak in Alabama.

Bad farming practices caused this unnatural natural wonder.

A nun spent 16 years painting the stunning Celtic mural that covers the interior of this WWI memorial.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The courtyard of this small Marinid madrasa is a dazzling example of intricate Islamic architecture.

Traditional 11th-century outdoor tannery.

Originally envisioned by King Ludwig II to rival Versailles, Herrenchiemsee's "New Palace" remains half-gilded for lack of funds.

France's Lilliputian park displays over 100 of the country's monuments for visitor perusal.

One of the most powerful religious centers in the Middle Ages, dubbed the founder of Western monasticism.

When you can't get to the Pacific, just go to Florida.

A historic landmark and museum filled with curious objects representing the history of Key West.

This small Key West museum is packed with dozens of artifacts that illustrate the life of the iconic playwright.

The museum chronicling a treasure hunter's dream, fulfilled.

The sign that drew attention to a young boy's cucumber stand is now the name of his fruit superstore.

The highway's southernmost spot is a beloved local attraction.

Found: Garden of Eden in Miami-Dade County, Florida.

This small museum gives visitors a chance to soak up the history of the "sponge capital of the world."

"We Seceded Where Others Failed."