It's been a while with no one responding so I'll add my two-cents here. Several that stood out for us in our travels. Although not limited to adults, there wasn't anything specifically set up to entertain smaller kids.Winchester Bay RV Park
. Located in the Reedsport Oregon area. Not limited to adults, but most of the kid activities were off-site. (Dune buggies etc.) We liked Winchester Bay as one could not run their sand quads back and forth in/out of the park to the dunes. Kept it quieter. We used it as a base-camp, drove up and down the Oregon Coast in the tow car to enjoy lighthouses, beaches, etc.Lewis and Clark RV Park
. This one is located in South Astoria. Much smaller than Winchester Bay and they are still building this park. Need to be self-sufficient as there's no laundry, bathrooms, showers on site yet. This couple is a delight. Great 9-hole golf course to putter around. Anyone with kids, generally camps at the amazing Fort Stevens area across town. Astoria kept us busy exploring for an entire summer and into the fall.Outdoor Resorts
Located on 101 in North Newport, Oregon. Show even the slightest interest in the place and they will comp you a couple nights in one of the owner sites. All kinds of amenities. There is an indoor swimming pool that would entertain kids, but we rarely saw any young families here. You may never leave...