This splendid Versailles-inspired mansion has the largest French-style formal gardens in North America.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

In which a local geological marvel becomes a quaint roadside attraction.

A museum dedicated to the quirky and colorful world created by Springfield's favorite son.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

A failed piece of Orientalism has become the proud symbol of a community.

A park full of outsider art, created by college students studying outsider art.

World's first "penitentiary," meant to be humane, drove men insane.

A layered tribute to the work of mosaicist Isaiah Zagar.

South Philadelphia is home to Keith Haring's only surviving in situ collaborative public mural.

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

Where America's first doomsday cult awaited the end of the world.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.