Largest Roman Catholic church in North America.

Home to items never before seen by the public.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

Controversially claiming the title of world's biggest bass drum, UT's Big Bertha was once made radioactive by the Manhattan Project.

The world's tallest statue of an American hero.

Famously misunderstood wonder of the ancient world

The longest hedge maze in the world.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

This one has sailed five times as far as Sir Francis Drake's famous ship.

Christ's blood preserved in a Belgian town.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

A little sculpture with a large wardrobe.

The famous winding walk at Chartres is surrounded in mystery and myth.

The mummified heart of Louis XVII, the lost dauphin of the French Revolution.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

Steadily reminding Czechia of its past.