Oldest building in California still in use.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

The now-serene site of the largest earthquake ever recorded in North America.

An outsider art duo's yard has been turned into a whimsical public gallery.

A huge collection of rocks, gems, and crystals.

A bronze tribute to a legendary Californian, the self-proclaimed "Emperor of the United States."

This 15-story mural celebrates the 50th anniversary of the musician's iconic "At Folsom Prison" album.

The second building of its name to occupy this location might be the finest flatiron building in San Francisco.

The California capital city once stood 10 feet lower than it does today.

Art Deco stylings conceal the true nature of this bridge.

Outsider art or homage to aliens?

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

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

Along the edge of this fountain are 365 smaller fountains that represent the days of the year.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

The final resting place for the remains of 143 Habsburg royalty.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

The Habsburgs' royal collections of art and wonders.

In the middle of a Vienna square, Roman ruins dating back some 2,000 years are on display.

A patriotic medieval knight in driven-nail armor raised money for widows and orphans of WWI.

Designed as a reminder of one of the darkest moments in Austrian history.

Legends surround an ancient tree trunk riddled with nails for good luck.

Baroque celebration of the end of the Great Plague of Vienna.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.