These azure waters were thought to lead to the Mayan Underworld.

An ethereal glowing blue ocean cave in Croatia.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

Millions of glowing microscopic organisms light up the waters of this luminous lagoon.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.

This museum boasts the ninth-largest collection of insects in North America.

This revered mutant tree was felled in an act of ecoterrorism leaving a legacy of myth and possibly murder.

Along a California highway is a kind of Jurassic Park made of metal.

Private collection of art inspired by cabinets of curiosity.

An Australian lake whose pink hue defies scientific explanation.

First a horse rendering plant, then a 19th century landfill, this beach is full of glass from thousands upon thousands of broken bottles.

Every autumn, this hillside is ablaze with red summer cypress.

38-story baroque tower reflecting Detroit's rise, fall, and possible rise again.

World-famous, Pink's still manages to keep its prized cult fetish status.

Home on the Hillside, and home of the first breakfast cereal.

A marvel of Byzantine engineering under the streets of Istanbul.

A curious blend of taxidermy, antique tools, creationism, and a purported antediluvian rock.

Largest cave system in Africa.

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