The two writers famously didn't come to blows over the Oxford comma.

Civil War-era Fort designed to withstand invasion and attack, with tricky traps called "murder holes."

At the supposed instruction of Ben Franklin and Socrates, a Spiritualist believer intended to birth a mechanical messiah here.

For 20 years, this whale skeleton has been slowly dripping oil on the floor of the museum where it hangs.

This peaceful Massachusetts graveyard was one of the first "garden-style" cemeteries in America.

Impossibly life-like natural history models created out of glass by a father and son.

"Mock all and sundry things, but leave the saints alone."

The headquarters in Salem doubles as an occult art gallery.

Experience the hysteria of a 17th century witch hunt through goofy reenactments and wax dummies that should probably be burned at the stake.

Mysterious stone tower featured in many alternative histories of the New World.

Three and a half miles of cliffs, rocky beaches, Gilded Age mansions and 40 Steps to nowhere in particular.

A crumbling stone stable and carriage house are all that remain of a manse that was once filled with Egyptian artifacts.

A violent name for a violent volcano.

The bat-covered home of one of the world's most popular brands of rum is located on a tropical Art Deco campus.

The site of the tragic isolation of Nipmuc Native Americans left to perish in King Philip's War.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

Legend tells how a Spanish soldier disappeared from this isolated sentry box without a trace.

France's most famous cemetery, with some of its most curious tombs.

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

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Tucked in the back of this amazing antique store is an important piece of medical history.

The biggest museum dedicated to insects in North America, one of the largest in the world.

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