"A hideous albatross in the Hudson River Valley."

Beneath the mossy overgrowth covering this once-sprawling campus lies decades of history and the secrets that come with it.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

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

A terrific purveyor of natural history objects and curios.

Before Nixon, "watergate" meant canals.

The most photographed house in Maine looks good enough to eat.

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

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

This Rhode Island mansion was a stand-in for the exteriors of Collinwood in the original "Dark Shadows" series.

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

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

A toxic ghost town sitting atop a massive coal fire.

A particularly creepy abandoned hospital that sparks interest for lovers of the supernatural.

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

This historic Pittsburgh tennis complex is a rare example of natural red clay courts.

This university transit system is a 1970's vision of the future.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

The site of the little-known Pennsylvania battle that sparked the Seven Years' War.