I know that area well. Reviews on Holly Lakes are accurate. Most sites are a LONG walk to the pool. Trap Pond State Park is a decent CG. They have no pool, but sites are shaded and have water and electric. They now have an upgraded dumping station. The park has a nice pond and trails, but no swimming. I am afraid you will have to drive more than 15 miles to get a DECENT CG with a pool. Fort Whaley and Island Resort CG's are nice, pet friendly, and have pools, but are 25 miles away. JMO, to make your stay more enjoyable. BTW, Millsboro is a very large area. Are you talking about the town area or Long Neck. I may have more options for you..