Cobscook State Park is beautiful. The park is big, and many sites are very far apart - we had almost complete privacy.  There are both reservable and non reservable sites.  Some sites have Adirondack shelters.  All sites have picnic tables and fire pits.  The majority of the tent sites and small rv sites, and some larger rv sites, are on the water.   We stayed at 2 different sites - a waterfront site and non waterfront - and both were scenic and private.   There is no water/electric/power at any site.  There are water stations around the park, as well as a bath house and dump station.  The park rangers are friendly and helpful. There is a lot of wildlife and waterlife - we saw many seals and cormorants in the water, as well as a few eagles.  You can launch a kayak from your campsite, or from the large  dock/boat launch area in the park.  Kayaking should be done with prior research to ensure familiarity with the tide changes (which are up to 20 ft) and currents, which are strong and dangerous in certain areas of Cobscook Bay.   There is a great map published by Cobscook Shores that shows recommended kayak areas and tide access.  It includes the launch that is in the park.  https://cobscookshores.org/wp-content/uploads/2021/08/CS-System-Map.pdf  

 There are also a few open areas for picnicking or just relaxing, as well as a play area for kids.  There are a few nice, relatively short and easy  hiking trails that run through the park.  One of the trails is right at the entrance, so you can park there if needed. For more advanced hiking, the Cutler Preserve land, Boot Head, and Quoddy Head are all nearby and offer incredible hikes of varying distances, up to 10 miles.  Quoddy Head also has a lighthouse that is a popular attraction .