A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

A kaleidoscopic warehouse-maze of handmade neon signs.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A lush green oasis in the middle of Chicago.

A Museum of Holography frozen in 1974.

Huge abstract sculptures of the Puerto Rican Flag.

New York's oldest magic store.

Elevated freight railway turned wildly successful urban park.

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

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

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.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

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

This little museum is built on a theater that was once a wildly elaborate speakeasy.

A hip bar decorated with walls of golden skulls.

A hands-on traveling collection of the innovative devices of yesteryear.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

Order scoops of pandan, lychee, and black sesame at this family-run institution.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

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