Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

Snack on a partially gestated duck egg.

This slender three-story building has also had several famous residents.

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.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

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

The "Seinfeld" diner.

France's most famous cemetery, with some of its most curious tombs.

This small plaza encourages people diagnosed with cancer to never give up hope.

An abandoned asylum incorporated into a college campus.

Rare recess caves fill this unbelievably beautiful Ohio park.

The last funhouse of its kind, where guests enter through the mouth of an 80-year-old blue whale.

This quarter-mile tunnel under the Bluff in Pittsburgh bends at a 45-degree angle.

When oil was discovered just outside of Pittsburgh, the city became home to this regional stock market.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

Don't get it twisted: This is the oldest pretzel bakery in the United States.

Memorializing an American tragedy of massive proportions.

This extraordinary Depression-era expenditure was modeled after a postcard of a Mediterranean hotel.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

Its vintage camera collection gives a snapshot of the past as viewed through a photographic lens.

This church in Pittsburgh is home to the largest collection of religious relics in North America.