I might suggest you consider staying at
Oak Grove Park. The campground is situated about 30 miles north of Philly. You can drive to the Philadelphia airport in about 60 minutes via the turnpike & the blue route.
The sites at Oak Grove are all level, nice size and is situated in a very pleasant, peaceful neighborhood. You have easy access to many of the historic, educational and amusement activities that your family would appreciate.
Click here just to view a few.
Tens minutes from the campground you can catch the train for a 55 minute ride into Philly. Then a 3 block walk to Historic Area.
The campground fees are very reasonable and it is not unusual for people staying 3 and 4 months. The place is family owned and very neatly maintained.
Hope this helps. If you would like more info please feel free to send me a private message.
