Elevated freight railway turned wildly successful urban park.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

A crumbling hospital from the 1850s on Roosevelt Island.

A terrific purveyor of natural history objects and curios.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

At Monet's beloved home you can still see the Japanese bridge, waterlilies, and weeping willows that were the subjects of some of his most iconic paintings.

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

This museum houses an imposing skeleton army comprised of creatures great and small.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

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

These imposing walls and towers look more like the ruins of a fortress than a monastery.

Ireland's most remarkable collection of these curious cone-shaped houses is worth the buzz.

Traveling this mountain pass reveals quaint stone buildings, stunning Irish scenery, and a bridge said to grant wishes.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

An unusual manor of stunning beauty, born out of a crippling disease.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

The pockmarks across the building's facade are remnants of the Blitz.

These mysterious Viking chess pieces spent centuries hidden on a remote Scottish island.

The "lost friend” is the most famous of the six moai statues that were removed from Easter Island.

Revel in the Victorian splendor of the world's oldest eating establishment inside a museum.