Why a column on the entrance is inscribed with a verse from the Quran is one of Sicily's many mysteries.

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

Every inch of this chapel is covered in craftsmanship from across the world.

Behind medieval walls in a corner of bustling Palermo is a breathtaking former mosque once inhabited by a wolf-taming hermit.

This mosaic-lined medieval church was built by the world's first admiral and still holds mass in ancient Greek.

Thousands of well-dressed mummies below a monastery.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Museum devoted to the artificial language of Esperanto.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Legends surround an ancient tree trunk riddled with nails for good luck.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

Baroque celebration of the end of the Great Plague of Vienna.

This Austrian museum celebrates the work of famous forgers and their inimitable imitations.

The final resting place for the remains of 143 Habsburg royalty.

19th century cemetery hidden in Brooklyn's Prospect Park.

More than 300,000 historical artifacts from the famous music venue, from Duke Ellington's handwritten score to The Beatles' booking slip.

Come for the waffles, stay for more waffles.

A massive forgotten storehouse from 1913 on the Brooklyn Waterfront has a spectacular view of Brooklyn.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

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

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

An engineering wonder at Pillnitz Castle protects a precious 230-year-old flowering shrub.

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.