A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

These mysterious ancient stone spheres were created by a civilization lost to time and are now mostly lawn ornaments.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

These medieval skyscrapers dominate the skyline of this small Tuscan town.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

Balconies that have a most unusual accent.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

Go inside to really appreciate this 500-year-old technological masterpiece.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

Climb inside an iron crystal magnified 165 billion times its normal size.

Mexico's astounding mummy museum with "the world's smallest mummy."

Bug-devouring flora are the stars of a special wing of the glass conservatory.

20,000 pieces in a Frank Gehry-designed building.

A museum dedicated to the exploring past, present, and future innovations.

Secret hideaway for an alternative beach experience.

The only arched bridge made of stone on the entire Mississippi River.

This striking art museum holds an amazing series of curiosity cabinets.

A place to eat for on-the-run agents and espionage enthusiasts.

An oddly poignant roadside attraction celebrating American folklore.

The magic's in the hole!

A huge musical instrument played by the ocean.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

DIY collection of eclectic holdings.