Stalactites and stalagmites in a beautifully lit cave.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A curious collection dedicated to human and animal anatomy and pathology.

Walk 2,300 feet above the ground on the "Troll's Tongue."

A surreal museum of extraordinary industrial objects.

Private collection of art inspired by cabinets of curiosity.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

A psychedelic labyrinth on the San Francisco bay.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

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

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

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

Fall down the rabbit hole into a surreal journey of human consciousness "from ass to soul."

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

Established in the '60s, a family-owned tropical drink bar founded by Ray Buhen, bartender to the stars.

A book collector's dream, this Toronto bookstore has the world's first "Biblio-Mat," a random book vending machine.

The world's only international cryptozoology museum is host to an unrivaled collection of mysterious objects.

The oldest hotel in the world has been operated by the same family for over 1,300 years, even catering to samurai.

An underwater city for the dead.

This South London cemetery holds the remains of more than 15,000 people.

An abandoned stretch of highway, deteriorating next to the operational one.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.