A volcanic tunnel illuminated by natural skylights offers a shaded respite from the desert sun.

"Polynesia on the Plains."

A cave 150 feet beneath Kansas City is the perfect climate for growing 10,000 delicate orchids.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

This "synagogue" is not what it seems to be.

Malibu's first beach home features an astonishing trove of ceramic tiles.

A common entry point to the Griffith Observatory trail holds its own wonders.

This former Mormon settlement is reemerging from the receding waters of Lake Mead.

Over 1.3 million confiscated wildlife products fill this macabre menagerie of illegal animal specimens.

The underground sanctuary of a mysterious ancient cult.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

The small sanctuaries lie just off the beaten path near one of Bhutan's most famous attractions.

A home built with marble tombstones from the graves of 2,200 Union soldiers buried in a Virginia cemetery.

The unique funeral practices of the Toraja can be seen here with graves carved into caves and hung off cliffs.

This isolated structure beckons adventurers with sublime views of the Faroe Islands.

The skulls and bones of thousands of soldiers line the walls of this small Italian chapel.

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

This everlasting lightning storm may be the world's largest generator of ozone.

A Buddhist temple to honor insects that died for science.

A desert that rolls right up to the ocean, where it's so dry animals live off the fog.

Only museum in the world devoted to bookbinding and book arts holds a permanent collection representing five centuries.

Duluth mineral magnates built this charming art deco lodge to be their private clubhouse.

The oldest bibliophilia club in America, with exhibitions on historic books and graphic arts.

A deadly ancient portal to the underworld.