Think of the Highlands as the "backyard" and "backstop" of the Philadelphia-New York-Hartford metroplex. A backyard that spans over three million acres across Pennsylvania, New York, and Connecticut, the Highlands serves as recreational open space for the metroplex's burgeoning human population. As backstop, Highlands' watersheds provide a ready source of high-quality drinking water for over fifteen million people.

The Highlands is the first book to examine the natural and cultural landscape of this four-state region, showing how it's distinctive and why its conservation is...