cape henlopen state park is located in lewes, delaware. there is a small fee upon entering the park, but it is per car rather than per person. i didn't have much time to explore and i spent most of my time warndering around the fort miles historical area and you can get a great view of fort miles from climbing to the top of the wwII observation tower. there are beaches and trails to explore, and i also found a wwII bunker (also like the one in cape may, new jersey, but this one was in the dunes rather than located smack in the middle of the beach). it was a bit chilly that day, so i didn't spend much time on the beach, i'm not a big fan of cold wind and there was plenty to be had.
i would recommend visiting in a warmer time of year so that you can take full advantage of the trials and beaches (which are amazing, by the way, very clean and white sand as far as you could see). and defintely take some time to explore the fort and it's history.
on to my next adventure...