An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

A collection of collections, including an anatomy museum, the “Cabinet of Physics of Alessandro Volta, a museum of natural history, mineral collection, and much much more...

This short bridge is the only thing connecting a tiny Irish island to the mainland.

Northern Ireland's Brobdingnagian stepping stones.

The atmospheric road was never meant to be so creepy.

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

The oldest inn in Kilkenny was established by the first convicted witch in Ireland.

The ancient tomb acts as a calendar that keeps perfect time.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

This single room has survived the centuries with almost no deterioration.

An old trolley bridge was converted into a breathtaking garden bursting with colorful flowers.

The largest self-built castle in the U.S., six decades in the making.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

A monument to the sheer amount of oddities one can collect over a lifetime.

A monument celebrating the idea of reaching inaccessible places.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

Former villa and estate of James Deering developed to preserve native tropical forests.

One-time winter retreats of prolific inventor Thomas Edison and his friend Henry Ford.

One of many gator theme parks, abandoned in the sugar fields of South Florida.

A Circus legend leaves an unexpected endowment.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Medicinal spa created with the discharge from a geothermal energy plant.

Old Danish castle immortalized in Shakespeare's Hamlet.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.