Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

A lush green oasis in the middle of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

The largest airborne operation in history was launched to capture this bridge.

A solid steel plane designed to catch fire over and over again.

This large open-air museum showcases the ordinary lives of the people of the Netherlands and pre-industrial crafts and practices.

This artificial ring island was built to hold cubic tons of polluted dirt.

Now a museum, this building was once a 14th-century monastery and the place where the founder of the Dutch nation lived and was assassinated.

This unique sculpture proved invaluable when it saved a train from careening off the tracks.

The Netherlands is home to a bridge printed out of reinforced concrete.

A journey through 430 years of bulbiculture in the Netherlands.

The birthplace of most all of Europe's space missions is here on the Dutch coast.

This hotel was once home to a steamliner company and became the final rest stop for Europeans heading to the New World.

The largest flower auction house in the world.

This fairy tale forest hides scenes from some of the more obscure and bizarre Western nursery stories.

The world’s first interactive human body museum also serves as a chair for a giant orange man.

This beautifully designed star-shaped fort was the premier defense system of the late 1500s.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

Colorful and chaotic stacked hotel in North Holland.

This cheese shop also houses a museum devoted to Dutch dairy.

Visit an imposing 13th-century Transylvanian citadel lurking not far from the region's more heavily touristed attractions.

This fortress-like monastery is covered with intricate frescoes.