There are so many wonderful trails within 300 miles of NYC that it would take too long to list. However, the best place to start is with the Appalachian trail. The trail runs from Mount Katahdin in Northern Maine to Springer Mountain in Georgia and offers "paths" that range from very difficult to easy. The site below has all the information you need. You might also look into the many trails running through the Adirondack mountains (2nd site below) as well as the relatively easy trails through Acadia National Park in Maine (3rd site below). Enjoy!
