This lab's maddening silence is good for business but bad for sanity.

The second-deepest known cave on Earth, hidden in an extremely remote mountain region.

An isolated dive site teeming with cnidarians.

Eighteen miniature death-scene dioramas.

An encyclopedic collection of mammal penises.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A 30-acre garden inspired by the principles of modern physics.

A fiery crater has been burning in the Karakum Desert since 1971.

The world's largest bioluminescent area was undiscovered by science until 2005.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

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

Some of the clearest water anywhere in the world.

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

Monasteries on rock pillars, once accessible only by frayed ropes.

The world's only complete colossal squid specimen is on display at the Te Papa Museum.

A single tree's 2,800 aerial roots give the appearance of a complete forest.

An enormous, inside-out glass globe built in 1935.

"World's largest scrap metal sculpture" stands in an outdoor sculpture garden in the middle of Wisconsin.

The lavish temple of the Cao Dai religion that includes Buddha, Mohammed, Joan of Arc, and Victor Hugo.

Seoul amusement park boasts a Korean-speaking pachyderm.

A salty red wasteland in Tanzania is a breeding spot for endangered flamingos.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

Stone shrouds of Prince Liu Sheng and Princess Dou Wan of the Han Dynasty, created to preserve their flesh for eternity.

One Costa Rican island is so beset by illegal shark poachers that the local rangers have built an entire bridge with their confiscated gear .