I agree on Yellowstone.We were there in May and it was the best trip we ever had. We were in the park for 4 days but could have easily done 6. There is so much to see and it's huge. We stayed in Madison Campground. No hookups. Mammoth Campground looked like the sites were a little more spread out. Madison was more centrally located but there was nothing close to the campground. At Mammoth you are right outside the Village of Mammoth Hot Springs which has a few places to eat,a visitor center and gas. You are also close to Gardiner Montana for groceries,gas and dining.
Black Hills area is nice too. Custer State Park is nice. Several campground some with electric hookups. Not too far from The Badlands and Wall Drug. We also liked Bear Country USA and The Cosmos.
From there I would head east.Many nice state parks to camp along the way. Most have electric hookups some as low as $16 a night. Each state is different as to their campgrounds but most are nice. We stayed at Waubonsi SP in Iowa for $16 a night with electric.Also Pershing State Park in Missouri for $19 a night with electric. Pershing is located on Missouri Rt 36 which is a great alternative to I-70.4 lane and 65 mph. We also stayed at Buck creek State Park just east of Dayton,Ohio off I-70. Beautiful park with electric and swimming beach. You are close to the Air Force Museum if you like planes. Keep going east to Gettysburg. We like Pine Grove Furnace State Park, about $26 a night with electric about 25 miles from Gettysburg.From there I would go to Assateague National Park. No hookups but the wild horses will come right into your campsite. Go to as many ranger programs as you can. From there head south to Shennadoah National park. Stay at either Big Meadows of Loft Mtn. The head south on Blue Ridge Parkway. I would recommend Sherando Lake, a national forest campground with electric hookups. Keep heading south to Goose Point Campground. They have some nice sites in loop C, some right on the water. From there I would head towards Myrtle Beach and stay at Huntington Beach State Park. Most sites are water and electric with some full hookups. Short walk to the beach.Visit Attalaya which is where the Huntington's lived who the park as named after. They also have great nature programs there. You are close to Murrels Inlet where you have some good restaurants like Drunken Jacks.
From there you can head to Florida and the keys. Curry Hammock State Park is nice with sites on the water with water and electric hookups.Have a great time.
