This natural sea cave hides a small wonderland of natural turquoise beauty.

A well-preserved network of cavernous tunnels have spent silent centuries removing Toronto's waste.

The Victorian-era greenhouse is stuffed with tropical plants, and open 365 days a year.

A botanically themed auditorium blooms within the world’s last operating double-decker theater.

This French Canadian classic is a specialty of the oldest continually used church in Minneapolis.

The world's largest collection of materials relating to lesbian history is housed in a Brooklyn townhouse.

A hidden architectural treasure in New York's Brooklyn.

A beautiful collection of architectural ornaments rescued from demolished New York City buildings.

Come for the sustainable organic chocolate, stay for the sustainable organic booze.

Volunteer-run library dedicated to exploring five decades of activism history.

“Invented in Key West, Perfected in Brooklyn."

Detailed facade of a brownstone in Boerum Hill.

Leaf through over 30,000 artists' sketchbooks in what may be the world's largest collection of doodles

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

This former Norwegian sailor's church is slowly being taken over by ramshackle robot musicians.

Sniff the Titan Arum's rotting flesh.

This 3,500 pound obelisk was constructed with more than 1,000 reclaimed guns.

An architectural statement of artistic intent smack in the middle of Providence, Rhode Island's Colonial uniformity.

A 19th century library favored by Edgar Allan Poe and H.P. Lovecraft, known by locals as "the Ath."

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

Paths are maintained, but trees have taken over plots.

An exquisite grouping of structures made from 10 tons of invasive saplings.

A view-altering observatory at the University of Texas.

A former electrical substation is now home to an eccentric junk art masterpiece.