A 19th-century subterranean reservoir repurposed as a contemporary art cave.

Bored potato-guarding Nazis etched their thoughts onto a brick storage building in Copenhagen's Meatpacking District.

The final resting place of one of the brightest physicists of the 20th century.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

The final resting place of the author who gave us the Little Mermaid, the Ugly Duckling, and many more beloved fairy tales.

Visitors are treated to a stained glass kaleidoscope interior inside this work of art.

The art museum is decorated with creatively remodeled pre-Nazi swastikas.

The gilded, masterful astronomical clock will calculate time, dates, and planetary positions for thousands of years to come.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

This sublime architectural marvel is a rare example of an expressionist church.

A restored Pittsburgh house of God has been converted to a marvelous house of suds.

The final resting place of the most famous sharpshooter.

This NASA test station is home to some of the world’s largest and most powerful space environment simulation facilities.

A county library in rural Ohio houses one of the finest mineral collections in the world.

During an annual Catholic feast in this tiny Spanish village, men dressed as devils leap over rows of babies to cleanse them of sin.

This line of 12 tower mills described in the story of Don Quixote is among the most iconic landscapes in Spain.

This abandoned, turn-of-the-century astronomy hub is now the subject of more photographs than it ever took.

This amended headstone marks the grave of a participant in one of the most successful military deceptions of all time.

This mountaintop observatory is home to one of the world's largest reflective telescopes.

The effect of this ancient form of image projection situated atop an 11th century Moorish palace is thrilling.

This lucky bronze frog was gifted to Madrid by a casino.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

Beautiful tiles decorate many of the town's surfaces and stand testimony to its glorious artistic history.

This overlooked museum houses an amazing collection of rare, antique typewriters.