From cartoon characters to tiny tanks, a guerilla sculptor's little bronze statues are hidden throughout the city of Budapest.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

These WWII-era murals were initially booed as a libelous portrayal of the American dream but have survived multiple attempts to have them destroyed.

Depicting scenes of everyday life - and specific individuals - in Great Depression era San Francisco.

Recovered from the brink of extinction, at home in the Financial District.

A pair of mutilated bronze octopuses slump at the base of the monument honoring California's admission to the U.S.

This 19th-century church is now a popular roller rink.

Fonts are born and bred here at the oldest letterpress type foundry in the United States.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

Early prototype for Frank Lloyd Wright's Guggenheim.

The first fresco Diego Rivera painted in the United States can be found in the former San Francisco Stock Exchange.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Tiki luxury on Nob Hill.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

Olfactory delights in San Francisco's Botanical Gardens.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

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