Abandoned limestone cave was once a sacred place of worship.

These bamboo and rope bridges cross the Nam Khan River for six months every year.

Breathtaking and huge 430 year old maps of Italy.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Furniture tries to escape an abandoned building in San Francisco.

Art from the latest counter-culture; kids who dye their hair blue and believe the future will be a post-apocalyptic water world.

An unassuming grey box sitting on San Francisco's Pier 17 is a "sky diary" of the coastal city's temperamental weather.

This eatery transports diners to a place that no longer exists: East Germany.

The United States' first transcontinental automobile road came to its end at this spot in San Francisco's Lincoln Park.

The oldest alley in San Francisco is paved with a reminder of the city's original shoreline.

This Alamo Square mansion is rumored to have hosted satanic rituals and other occult practices.

This teeny-tiny park built by a San Francisco man in 1962 is mostly stairs.

A quiet marker in memory of local men and women lost in WWI.

The oldest lawn bowling club in the United States.

Overflowing with shipping containers, this location has been transformed into a massive workspace for artists.

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

A former hardware store near Yerba Buena is the official home of California's history.

One time home to turn of the century explosives, now hidden under the Bay Bridge.

Built in 1906, this unique building was the first Hindu temple in the United States.

Over a century old, this restored Victorian building is surrounded by a lush garden filled with rare palms.

At the base of the Golden Gate Bridge, a small sign basically begs for a high-five.

The original place where water met land in the City by the Bay is outlined in brass.

This contorting sculpture is the tallest in San Francisco.