The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

It took 82 years and four different plaques to finally get the story right.

A backdoor to Machu Picchu that only the most foolhardy infiltrator would attempt to breach.

This is why we can't have nice things on the Incan Trail.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

Huge stone depressions which may have acted as an Incan agricultural experiment.

This Peruvian canyon is filled with geometric salt pools that have been being harvested since the Incan empire.

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

This monument on Breed's Hill proves that one of the most famous battles of the Revolutionary War is misnamed.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

Palatial mansion estate used in films including "Flowers in the Attic" and "The Witches of Eastwick."

An 80-year-old house built out of newspapers.

Friction between grains of sand cause a curious "singing" sound.

A New England ghost town features a trail of boulders etched with intriguing life lessons.

An eccentric inventor's castle home with its own indoor weather system.

In Gloucester, Massachussets, fishermen celebrate a successful year at sea by charging a lubed pole to capture an Italian flag.