We went in spring 2003 (IIRC) and did not leave Tulsa until rains had been in the area for a week or more. That made all the difference because everything was in bloom. I kinda used the NOAA site to watch the winter/spring storms come into and through that area. Staying in the park is doable but pretty desolate on the river and the mountain camp grounds are just that; in the island mountains. We choose a commercial campground in Alpine and made big loops to the park: lots of driving but more amenities and neat things in the area to see and do. Again IIRC that road to the Rio Grande campsite on the East side of the park rte 20, is/was 20 something miles of dirt road. There is a road on the West of the mountains that goes to the river (Santa Elena canyon) but I do not remember campgrounds on that side, may have changed though. The West side road is long, lots of elevation change and long, with nothing much but scenery, and did I mention long. Oneway in and out unless you want a very long stretch of back country dirt road, that I would not recommend unless extensively rigged for roughing it. There is a commercial resort type place on the West side outside the park on the river around Terlingua. As I remember it that place has the only green outside the mountains all the way West to Presidio on a farm-to-market hwy. The only services (gas mostly) is at the junction in the park, and in the year we were there fuel was over four bucks so I would anticipate VERY high prices for anything inside the park. Nearest wallyworld is Ft Stockton. Don't forget the Marfa ghost light. Only other thing is, that is huge country and driving long distances is very much a part of the trip, with miles and miles and miles of desert/yucca interrupted by similar scenery. The BB Ranch Park West of BB Park has no amenities IIRC. Border Patrol was on heightened alert while we were there and they have check stations on the way out of the park and other roads that lead away from the border, stopping mandatory and since I had a cover on my pickup bed they pretty much went through it every time until I started leaving the park admission receipt on the dash and then they looked at it and waved me through.