Built by crowdsourcing, this wooden foot bridge saved a part of Rotterdam that was languishing in wait of city funding.

The eroded core of an ancient volcano is now accessible by a short hike.

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

The story of Two Guns, Arizona could easily be described as a Shakespearian tragedy on Route 66.

A spiritual vortex among the red rocks in Sedona.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

Dinosaur eggs were first discovered at these fiery red cliffs.

Mongolian Buddhists believe this monastery in the Gobi desert to be the center of the world's spiritual energy.

With a facade that measures just 107 centimeters, this five-story building is one of the skinniest in Europe.

In the fictional world of Kcymaerxthaere, standing at this site just outside Vienna, Austria, the sky would have been found beneath your feet.

Croatia's "hairy stone" fortress is one of the most well preserved Istrian castles.

A well drilled into the side of a cliff supplies most of the water consumed on the island of El Hierro.

1920's reinforced concrete church by architect Auguste Perret changes the face of modern design.

Designed to celebrate more than a century of circus performances in Australia.

This unique architectural wonder is home to luxury apartments.

Hidden just under the waters around this Turkish island are the ruins of a once great city.

A mysterious ancient cemetery with Roman sarcophagi and Lycian inscriptions.

The site of the first medieval crusade that pitted Christians against Christians.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

A colorful piece of contemporary art cheerfully clashes with Lyon's historical architecture.

Hundreds of hidden passageways weave through the old quarters of Lyon.

A tiled, multi-level garden of survival in Lyon.

Now in ruins, this castle stood for centuries and saw a number of gruesome events.

A retired tobacco farmer's pet project turned into a sturdy miniature city.