Once strictly off-limits, this lower level housing curious and priceless vehicles of the Petersen Automotive Museum is now open to the public.

The illuminating collection of L.A. street lights is run by the city and only opens one day per month.

Giant scissors seemingly stabbed into the side of a hair salon leave no question about the vocation of the owners.

A few iconic structures are all that remain of America’s first outdoor shopping mall.

America's most famous piece of self-built architecture.

This ultra-modern home clings to the slope of the Hollywood Hills on a precarious stilt.

This weird abode has inspired everything from the "House On Haunted Hil" to a robot hunter's pad.

Beautiful Victorian buildings from L.A.'s forgotten architectural past.

A castle that was built stone by stone by an eccentric journalist.

Established in the '60s, a family-owned tropical drink bar founded by Ray Buhen, bartender to the stars.

The oldest residential street in Europe also features an optical illusion.

Abandoned railway line circling the city of Paris.

This centuries-old hotel hides a network of secret cellars and passages once used by smugglers.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

An abandoned 1930s gas station turned bustling neighborhood park.

If there's another drive-through golf-cart bar in a bat-filled cave on top of a mountain, we don't know about it.

A 115-year-old restored German dining hall awaits those who venture beneath the Minnesota State Capitol.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

Super-heavy Nazi architectural experiment.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Started as a kitchen garden, now the second largest botanical garden in the world.

A collection of abandoned typographic signs from Berlin and beyond.

The most visited, and possibly most controversial, museum in Germany.