A cheeky architectural easter egg.

Decades before the scandal, this staircase on the river was a literal "water gate."

Leave a button on the jacket of this iconic Seattle clown.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This futuristic bridge is one of the longest self-anchored pedestrian bridges in the world.

A peculiar clock commemorates a historic victory won by ringing the noonday bell an hour early.

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

Ancient serpentine sacrifice holder that has stood the test of time.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

A wall of chewing gum moonlights as collective art.

This modest marker near Notre Dame identifies the very center of Paris.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This beautiful, historic church looks like something out of a simpler past.

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

This stunning concert hall has become a symbol of Iceland's national recovery.

For over 300 years this little carving has been the city’s good luck charm.

Yo, Adrian!

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

The most decorated dog of World War I is preserved in the Smithsonian.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

The best-preserved Roman small town in North Africa.