This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

Less a museum than a bizarre fantasy world created by artists and engineers.

The second oldest continuously operating bar in Louisiana.

The world's longest known cave system.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

The first declared National Monument in the United States.

Home to items never before seen by the public.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

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

World's first "penitentiary," meant to be humane, drove men insane.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.

The fairy tale castle of the "fairy-tale king."

Iceland's tribute to its thankless civil servants.

Cairns built to bring travelers good luck stretch across the land like miniature stone mountains.

This wrecked airplane has been sitting on a black sand beach since the 1970s.

An encyclopedic collection of mammal penises.

Walk in the footsteps of the gods and straddle two tectonic plates.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This bird-loving brewery is situated in an old municipal bathhouse, nestled beside a 300-year-old windmill.

Amsterdam's former hotspot for public executions and dissections.

Brussels' favorite peeing boy has a sister.

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Climb inside an iron crystal magnified 165 billion times its normal size.