The massive, incredibly rare instrument is over 11 feet tall with a range so deep it goes lower than humans can hear.

Eat your Big Mac in a DC-3.

This small Slovenian town has become a magnet for microbreweries.

Sculpture park built by a 50-year-old widow.

Despite many attempts to finish this overpass, it has been abandoned since the 1970s.

This modern arts center is built around a gem of late-Baroque architecture.

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

Decommissioned NYC subway cars are dumped into the ocean to create this underwater wildlife habitat.

One of the oldest surviving Swedish-American homes in the United States.

A scenic fort on the harbor protected Philadelphia from an attack that never came.

An exquisite Baroque church in Vienna's old town.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

This museum promotes informed contraception by documenting its often secret past.

Artfully arranged bones of 5,800 Austrians.

A spherical "micro-nation" in the heart of Vienna.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

The massive machine creates cracking displays of indoor lightning.

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.