A toy store with a century-long history preserves the craftsmanship of playthings of the past.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

The largest of London's subterranean rivers and once a mad, bad center of London life.

Dictionary Johnson’s favorite feline.

The home of 1.5 million wood letters for printing is still a functioning workshop.

A 100-year-old chair with joints "cemented by nature."

The legacy of an unsolved, gruesome murder rests beneath the spans of this historic bridge.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

At Chicago's revered Field Museum, visitors are invited to learn about and literally explore DNA.

The 606 is a decade in the making.

A giant bronze coil of feces is both a tribute to doggie defecation and a reminder to pick it up.

The final resting place of the world's first nuclear reactor.

Northern Ireland's Brobdingnagian stepping stones.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

A living archive of urban activism and space reclaimed.

A park with one large cat sculpture and 15 smaller ones, all painted by different Colombian artists.

The self-proclaimed world's smallest museum, located next to a Massachusetts sandwich chain.

The ancient settlement attracts tourists from all over looking to learn about the Chinese vision of the afterlife.

Enormous underground chamber built to detect 'ghost particles' of the universe.

A natural gas leak provides a flickering flame beneath a waterfall.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

An otherwise quiet campground becomes a bustling medieval town for two weeks every year.

A museum and doll store featuring a surreal and super sanitized version of where babies come from.

A curious whirlpool formation supposedly capable of entangling or engulfing branches, tree trunks, or whole rafts full of hapless tourists.