Less a museum than a bizarre fantasy world created by artists and engineers.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

A lake with hundreds of ancient skeletons surrounding it. The surprise is what killed them.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

This beautiful natural train tunnel is said to grant the wishes of visiting lovebirds.

Yale University's home for rare works, including the mysterious Voynich Manuscript.

The "world's biggest dinosaur" once housed a creationist museum in its abdomen.

A reproduction of earth's many biomes.

This woodland architectural installation acts as a camera obscura for the heavens.

Olfactory delights in San Francisco's Botanical Gardens.

The celebrated eyesore created by starry-eyed sweethearts.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

The ancient tomb acts as a calendar that keeps perfect time.

Renaissance villa and gardens complete with a tormented colossus.

The one-stop shop for all of your superhero (or evil arch-nemesis) needs.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

Abandoned bridge hidden deep in the San Gabriel Mountains.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

The last of its kind in the country.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.