Antiques by the Bay.

A winding path built in secret on the edge of the continent.

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

Concrete strongholds stand guard over the Golden Gate.

A haunting, yet lovingly hand-hewn potters' field full of graves that flood with each heavy rain.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Surrounded by low rise buildings and partially converted into an auto body shop, this marble archway is the only vestige of a forgotten Manhattan estate.

Visitors to this library are in for a real-world education in modernist architecture.

Small monoliths of several varieties of stone sit alongside a wooded path in the Bronx.

"Purveyors of traditional sweets and vintage treats."

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

Macabre astrological automaton clock dating to the late 1400s.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A once grand hotel is being retaken by the wilderness it once capitalized on.

The bones of an old zoo crumbling in the shadow of a new one.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

A wild west scene starring life-sized wooden statues hides in the trees behind Pierce College.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Lie in a hammock where George Washington stood.

This abandoned seaside fortress is now simply an imposing ruin being taken back by nature.

A graffiti Mecca welcoming artists from around the world.

Mysterious 500-year-old tapestries depict a unicorn hunt.

First a horse rendering plant, then a 19th century landfill, this beach is full of glass from thousands upon thousands of broken bottles.