Quite possibly one of my favorite out of the way places. Best part is you can drive right up to the pillars. And there is a good chance you will be the only one there when you visit.
We stopped by on our way home from Denver, Colorado in 2006. From central Oklahoma it is probably a little more than a day trip. It is, depending on the route, 7 plus hours from OKC. We came home through the panhandle of Oklahoma the time we last saw it.
Thanks for reading, take the road less traveled, and Happy Rovering.