Book excerpt: Pennsylvania is one of the best places to go birding in North America. From the shores of Lake Erie in the northwest and the great river basins of the Ohio, Allegheny, and Monongahela to the central Allegheny Mountains and east along the Pocono Mountains and the rich farmlands and rolling hills of the south, the Keystone State has a great diversity of birds. The American Birding Association Field Guide to Birds of Pennsylvania includes more than 275 species birders are most likely to see in the commonwealth. Illustrated with hundreds of crisp, color photographs, it includes descriptions of each birds along with tips of when and where to see them, written by an expert Pennsylvanian birder. It's the perfect companion for anyone interested in the amazing diversity and beauty of Pennsylvania's birds.