Collapsing castle on the Hudson river was once the storage site of military surplus business.

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

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.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

Hellam Township is reputed to feature seven remote gates, which when passed through in the right order, open an entrance to hell.

A layered tribute to the work of mosaicist Isaiah Zagar.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

Dramatic river bend surrounds a natural red-rocked pedestal.