If Amtrak is too high-priced and you can get from Philly to the Trenton Train Station, you can take NJ Transit right to Penn Station. You'll probably want to call NJ Transit to find out when the express trains are from Trenton to Penn Station. They might stop at Hamilton first. Remember this if you ever want to fly out of Newark too. The train to the plane is wonderful. I live in Lawrenceville, NJ.