Fantastic find. Probably over a 100 sites and only a few taken. Great access to Niobrara River. Folks in office are helpful and low key. Pick a spot under trees, in open, and/or by river. Sites have fire pit and table. Nice shower rooms and flush toilets. Covered table area by office.
$12 per person (kids less or free, I can't remember).
A number of sites with electric for $10 more.
Lots of people floating river. Turkeys, racoons, birds, and deer.
Seems even if you pull in late, just sign a waiver by office door, and pick a spot and take care of details in morning. Camp sites go west of office but also meanders east for at least 1/2 mile down by river. Awesome and quiet.