The undercroft is a spectacular example of medieval Cistercian architecture.

Hitler's bleak vision of relaxation still stands as a mostly abandoned 10,000-room resort complex.

A national collection of Communist-era musical posters.

A Christian retreat founded to welcome refugees fleeing from the Nazis during World War II.

One of the largest amphitheaters in Europe is a former Nazi gathering place that still stands today.

Once a giant gingerbread factory, this space now hosts exhibits and workshops on the historic treat.

Warsaw's fantastically preserved gasworks...almost.

This uber-quaint Polish village is known for its habit of painting elaborate floral motifs on just about everything.

Curtiss is a forgotten figure in the early history of flight.

Every year model trains zip through a miniature New York City that's now 150 landmarks strong.

A hamlet full of permanent Christmas spirit holds one of the earliest theme parks in the United States.

Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

This small museum is an eccentric shrine to boyhood in the 1960s.

Even Henry David Thoreau found this glacial pothole irresistible.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

A beautiful 62-acre Catholic shrine and botanical garden.

The childhood home of one of Ohio's favorite sons, pilot and war hero Eddie Rickenbacker.

Inside the unassuming cemetery chapel is a magnificent stained glass window and mosaics.

Featuring one of the most complete and original collections of Presidential memorabilia, this is the site of the last front porch presidential campaigns.

This recycled wax museum may be the only one that features John Travolta in a Bible scene.

One of the largest collections of holy relics in the country.

This presidential tomb was not dedicated until years after Harding's death due to personal controversy.

An old church full of restored Catholic statues is a makeup artist's labor of love.

Home of the golf club used by Alan Shepard on the moon, and more artifacts from the sport's history.