Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

The 340-year-old house that inspired the classic Nathaniel Hawthorne novel.

Statue in Salem of the woman who starred as the witch Samantha in the sitcom "Bewitched."

Shelves covered in dozens of coffee bean varieties fill this North End institution.

Each August, one of the largest religious (and food) celebrations in the country is held in Boston.

An interesting decoration on this historic site, this weathervane comes with as many legends as it does questions.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

A plaque memorializes the Boston location of one of the largest nightclub fires in history.

The Battle of Atlanta in 360 degrees, featuring a corpse that bears a striking resemblance to Clark Gable.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

The prototype for all Nazi concentration camps.

One part antique store, one part curiosities hodge-podge.

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

This massive store is home to an eccentric collection of vintage, retro, and peculiar goods.

Civil War soldiers, captains of industry, and paupers all interred on historic grounds.

Art deco landmark on the outskirts of Washington, D.C.

A 60-room castle constructed by a horse-racing heir.

An eccentric inventor's castle home with its own indoor weather system.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

This quirky curiosity shop takes its cues from the world's bazaars.

Infamous marsh filled with toxic waste, World War II-era London rubble, and dead mobsters galore.

Why have you never heard of the second most popular tourist site in New York?

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.