Elevated freight railway turned wildly successful urban park.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.

Possibly the world's smallest museum is home to one exhibit that sheds light on the capital city's dark criminal history.

The U.K.'s first underground railway line is now a lively thoroughfare for runners and cyclists.

Protecting the dead from opportunistic body snatchers.

A verdant 17th-century-style garden hidden along Edinburgh’s Royal Mile.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

A secret garden in a picturesque Edinburgh village has inspired artists for centuries.

Come for the oysters, stay for the priceless art honoring inventors across history and Scotland's favorite outdoor sports.

An American ghost town hides along a side street in Scotland's capital.

The taxidermy remains of the first mammal ever cloned from an adult cell are on display in Edinburgh.

A book bound in the skin of an infamous criminal, along with countless other specimens.

Near the former site of numerous witch burnings, this lavish Edinburgh mainstay pays homage to Scotland's brutal history.

Tiny effigies of the victims of Edinburgh's famous Anatomy Murders.

This waterfall is one of the most spectacular natural features in the Scottish Lowlands.

A secret door leads to this cozy dive that sells only “milk.”

A scattered trail of street art adds a pop of color to the city's stark structures.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

Saintly bones pressed into a wax effigy of a Catholic superstar.