The Pennsylvania State Park system is comprised of 116 parks and a grand total of 7000 campsites. Wherever you are and whatever your preferences are when it comes to camping there is likely to be a site within one hour distance of your location.
Where to Camp
It's important to mention that each state park has its own rules when it comes to camping, and while some allow you to pitch a tent pretty much anywhere you want within the park, others have very specific rules regarding overnight stays. This means you may be required to reserve a space or you may be limited when it comes to the areas you're allowed to settle in. The Clear Creek State Park and Ohiopyle State Park are two examples of parks with very relaxed rules. Because they're popular destination for canoeing and white water rafting, camping near the water is allowed, as well as pitching a tent at different spots within a single stay.
The area known as Pennsylvania Wilds located up north and inland, has the most campsites, with facilities ranging from modern, with flush toilets, showers and electricity, to rustic, tent-only places. You can call toll-free 888-PA-PARKS to find out which specific parks are open at any given time. Most campsites are dog-friendly as long as you let them know in advance.
When to Camp
Camping season in Pennsylvania's state parks extends from late May to mid September. Most parks close at sunset, so you need to make sure you are already inside, with an assigned campsite by that time, or you risk having to sleep in town. During the summer season camping is limited to 14 consecutive days (21 at any other time) and there may be some other restrictions depending on water quality or weather conditions. You can always check in advance by visiting the official website of the Pennsylvania Department of Conservation and Natural Resources and accessing their official list of campsites by region, as well as detailed warnings and tips for each area.
If you want to be on the move, three Pennsylvania state parks allow backpacking: Laurel Ridge, Moraine, and Raccoon Creek. This means you can actually stop for the night wherever you want instead of at an assigned campsite. Laurel Ridge is the largest of all areas, with 240 tent sites and 40 shelters along the way. Moraine, on the other hand, has no official tent sites, so you can actually camp overnight anywhere you please. With 16,725 acres of forests and lakes at your fingertips, it shouldn't be hard to decide on a spot. Raccoon Creek is a much smaller park of over 7000 acres with a large number of camping options: 172 campsites for either tents or trailers. When backpacking through these parks, you may need a special permit or at least a reservation if you're planning on sleeping on one of the designated sites, which can be obtained from the Pennsylvania Department of Conservation and Natural Resources.