Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

An artsy hidden staircase leads to breathtaking views of San Francisco.

A sharp bend in a dramatic river canyon cut through red rocks.

Most-visited and most-photographed slot canyon in the American Southwest.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

In a city filled with Frank Gehry buildings, one stands out as one of the architect's weirder works.

Crammed inside this grounded passenger plane is a bar that was once a Communist hang out and is now a ratty relic.

This former atomic bunker is now the Olomouc Institute of Remembrance, telling stories of the communist era.

The first designer power line in Estonia.

Mysterious craters may have been home to an ancient cult.

Latvia's symbolic mountain-shaped national library is home to millions of cultural tomes.

The oldest housing complex in Riga is a mini timeline of architectural trends.

A black cat protests the City Guild in Riga's Old Town.

This celebration of Latvia’s freedom and independence avoided demolition over half a century of Soviet occupation.

An old hill fort covered in over 100,000 crosses is a symbol of Lithuanian nationalism and beliefs.

3,000 market stands in five former Zeppelin hangars.

During the Soviet era, the spire of this longstanding church was used as a radio transmission tower.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

This insurance company building reminds customers that witches, bears, and gnomes are out there, best be insured.

The tiny, studious rodents greet visitors to the National Archives of Finland.