We were at Lincoln State Park in the Summer of 2015 for several days. It's a very nice campground, and the swimming area is within easy walking distance. From what we saw, there are no bad campsites anywhere. All of them looked adequate to fit our camper, and ours is 35 feet long. Roads and campsites are paved and gravel, lots of trees, lots of space for kids to play.
We did not go into Lincoln City, but there was lots of other things that kept us busy while we were there.
Here's a link to the Reserve America site with more information on the park and campground amenities
Click here.Also, check out the Indiana DNR web site, "camping" ... "Lincoln State Park."