The martyr's wax-enhanced skeletal remains lie preserved in a glass case in the Santa Maria della Vittoria in Rome.

This remote Colorado canyon is home to the second-largest collection of natural arches in the world.

This observation tower is one of two of its kind that still exist in the United Kingdom.

This secret Swiss fortress is disguised as a harmless pink house, complete with fake windows.

Considered one of the most haunted places in Europe, this 800-year-old castle was home to noble prisoners.

A 17th-century bezoar, dirt from an infamous site, and other curios decorate this unusual bar.

This letter written by Queen Elizabeth II in 1986 won't be opened until 2085.

This chestnut box will not be opened until the country music legend's 100th birthday in 2046.

This elaborate High Victorian Gothic structure is one of the world's few 16-sided buildings.

A big museum full of little worlds.

Edinburgh’s version of the Sistine Chapel is this former church, with an interior covered in paintings done by one woman over the course of nearly a decade.

Internet rumors, often involving Icelandic singer Bjork, have abounded regarding this isolated outcrop of rock.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

The awe-inspiring ship from the golden era of cruising has an incomparable history and a reputation as one of the world’s most haunted places.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

Over 100 towers were built in Bologna during the Middle Ages, but only 22 survive.

Long before Europeans arrived, Native Americans built an artificial island out of shells that has withstood a millennia of hurricanes.

The home where a lovestruck Fitzgerald wrote his first published novel, "This Side of Paradise."

A life-sized recreation of the megafauna that once roamed this region is a feature at the birthplace of American paleontology.

The largest treasure hoard in Europe is contained in a castle that was bombed out during World War II.

This historic Victorian mansion is allegedly so haunted that a signed waiver is required to enter.

Below this enormous headstone lie Billy and Benny McCrary, better known as the "McGuire Twins."

An unusual house built using an iso-elastic membrane.

The site of a tragic massacre that spawned a multimedia franchise.