This WWII-era military installation once held an entire city within its walls - now, its walls are falling down.

This whimsical stacked cabin looks like something out of a children's book.

This Alaska library may be the only one in the country that allows you to check out pieces of taxidermy.

Where Venice's gondolas go for a tune-up.

The marble facade hides a little-known medical museum with early surgical instruments and rare copies of canonical texts.

In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

The only museum with its curator—and her pets—buried inside.

An incredible menagerie of more than 3 million taxidermied animals at the oldest science museum in Europe.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

100 year tradition of fist fights, marked by marble footsteps.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

An intricately carved Viking church overlooks a glistening fjord.

Longest road tunnel in the world features an air treatment plant and the illusion of daylight.

A thin pane of glass keeps visitors from sliding off this futuristic skywalk.

One of the most breathtaking railways in Europe also takes one of the steepest climbs, from fjord to mountain plateau.

Walk behind a 50-meter-high waterfall.

The former home of Norway's greatest romantic composer.

The burning of this 12th-century church kicked off a campaign of Norwegian Black Metal terror.

St George's Leprosy Museum depicts the gruesome afflictions of those suffering from the disease.

A favorite with sightseers, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

An annual extravaganza of Broadway theater memorabilia.

The 28-foot granite map plots the locations of 40 theaters in New York City.