According to the internet, there was more than one campground here but I did not find that to be the case. There was only one area that looked like it might be a campground but there was no sign anywhere with the name of the alleged campground. 

I camped where another man had set up his tent. There were relatively clean vault toilets and some picnic tables. You could hear the road from this campground.

Free campground

Got to this site around 1 am and set up for the night. It was clear and dark enough to see the Milky Way. I slept out in the open and fell asleep looking at the stars. Mosquitos didn't show up at all despite it being late May. No running water to be seen but the pit toilets were reasonably sanitary and there is the pond (or is it a lake?) on site. Only one other cper was there. This is BLM so it is free. One of my favorite camp sites, and I camp a lot. Picnic tables, burn pits, trash receptacles on site. Fishing piers, and the water can be approached from several different areas.

There is fascinating and touching history here and I highly recommend a visit to the Black Kettle Grasslands as well as the Washita Visitor Center. It was my favorite park visitor center of the 32 I've been to in the last 6 months.