*shakes head* Pay no attention to those sending you north. You can hike and camp in the Chickasabouge Park right here in Pritchard/Saraland. And over in Baldwin County you can also hike and camp at Blakley. There are a number of trails over there. But with the river up you had better have a pair of gortex boots. Blakley is a state park as is Gulf State. Gulf State has a really good paved trail and a few around the campground. You can also go to Fort Morgan at the end of the Peninsula in Baldwin county for some history.
Those places are great for dayhiking but you cannot camp on any of those trails. As of right now there are no places to backpack in Mobile and Baldwin counties.