If astronomy had a ghost, it would look like this observatory.

This historic hotel invented the chocolate brownie.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

All of Chicago's wood-paved streets are long gone but two alleys remain.

The site of a 19th century "dream city" that almost rivaled Chicago before being swallowed by the Indiana sand dunes.

A chilling disappearance (and rescue) of a child uncovers a geological mystery.

Wisconsin's most celebrated export gets the royal treatment on I-94.

This national park on the shore of Lake Michigan features remarkable dunes that lie at the heart of a Chippewa legend.

This freshwater spring fills with 10,000 gallons of water per minute.

Ice cream stand, snack bar, and time capsule of milk conveyance.

Historic Hull Street was actually the first street with a proper name in the Boston area.

The site of Paul Revere's historic two lantern warning.

Dim sum, served in a grand old theater.

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

Three prestigious academic collections come together to create a world-class natural history museum.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

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

The eccentric mansion of one the most popular horror authors of modern times.

Around 100 sculptures from artists all over the world decorate the hiking trails surrounding this locale.

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

The 340-year-old house that inspired the classic Nathaniel Hawthorne novel.

Statue in Salem of the woman who starred as the witch Samantha in the sitcom "Bewitched."

The only structure left with direct ties to the Salem witchcraft trials of 1692.

A beautiful Victorian-era cemetery, complete with a miniature village.