The world's longest known cave system.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

An ancient capital city that dates back 3,000 years old and harbors many surprises.

Where manatees are the snowbird vacationers in these balmy Florida springs.

An underwater city for the dead.

Odd outsider art installations surround a Gold Rush-era ghost town.

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

The ghostly remains of an accidental sea.

The oldest cemetery in New Orleans, resting peacefully for over 200 years now.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

The rocks in this arid basin leave trails of movement behind them.

A museum and shop on Bourbon Street located in the former home of the second Voodoo Queen of New Orleans.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

A 200-year-old bar in the historic French Quarter refuses to give up its place in history, nor its role in securing ours.

The United States Capitol's former columns still stand.

A 100-year-old purveyor of curiosities, curios, and kitsch featuring mummies, shrunken heads, and a Fiji Mermaid.

A collection of oddities including Dr. Kevorkian's suicide device, the Thanatron.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

The final resting place of New Orleans' most famous voodoo priestess.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Medical and zoological curiosities for sale.