One of my favorite places to run in the Lehigh Valley of Pennsylvania is the Lehigh Parkway. It is a beautiful stretch land that follows the banks of the Little Lehigh Creek. It provides a great crushed stone path for running and walking as well as large fields for many other activities. It is a utopia plopped right in Allentown and is home to many local races. The link below is a great article by Frank Whelan that describes the history of how the park came to be.