According to the Big Bend Ranch State Park (BBRSP) website....."Welcome to the Other Side of Nowhere! Big Bend Ranch State Park offers outdoor recreation for the truly adventurous. This remote park features rugged mountains, steep canyons, amazing views, unparalleled night skies, and solitude in a high desert setting. The park stretches along the Rio Grande in far west Texas, on the U.S.-Mexico border."
"Visitors can hike, mountain-bike, backpack, paddle, ride horses or explore by vehicle (the park has two- and four-wheel-drive roads). This is Texas’ biggest state park, so there’s a lot to explore!"
"The park has 238 miles of multi-use trails (for hiking, biking and horseback riding). Visitors can explore 70 miles of unmaintained dirt roads in high-clearance four-wheel-drive vehicles. The Rio Grande/Rio Bravo area offers great day-use access. Visitors can float, fish and hike, or drive the scenic Camino del Rio (FM 170)."
"Campers can choose from vehicle-accessible, backcountry or equestrian sites. All sites (except backcountry) can be reached by vehicle. Some roads require four-wheel-drive or high clearance. Campsites offer solitude and great vistas; all (except backcountry) offer some camp amenities. Lodging is available at the Sauceda Bunkhouse."
"The park also has a 5,500-foot paved airstrip. If you plan to fly in, read the park's airstrip and aircraft guidelines (PDF), and be sure to call ahead to get up-to-date information and let park staff know when you will arrive."
Having been to Big Bend National Park a few times, we wanted to check out BBRSP. It's far less visited than it's "big brother" and offers much of the same scenery, is more rugged, and certainly more remote. Our initial plan was to camp at the highly coveted Churro Vista site. All the park employees that we talked with in preparation for the trip said things like "Wowwww... You got Churro Vista. Awesome!" However, upon checking in at the Saucedo visitor center and inquiring about hiking trails, things to see, etc., it quickly became apparent that we'd end up doing a lot of 4x4 driving (read : 5 miles/hour) if we stayed at Churro Vista as it's at the "end of the line". We were fortunate that a more central campsite was available and pitched our tent at Papalote Nuevo. Maybe Papalote Nuevo didn't offer the incredible views as that of Churro Vista, but they were still impressive.
In the interior of the park (i.e. not on FM 170) there are 35 - 40 individual campsites. We certainly didn't see many of these 35+ campsites, but those that we did see were far from the road and offered complete privacy. Up to eight people and two vehicles are permitted at each site. Most have a fire ring, picnic table, and shade structure (Papalote Nuevo did not have a shade structure or any trees to speak of). There are no toilets or water at the sites and all waste must be packed out. The roads to the sites are not paved and many require a 4-wheel drive, high-clearance vehicle. Check with the rangers to get more details on which sites are suited to your particular vehicle.
I should point out that the folks and amenities at the Sauceda visitor center were exceptional. The rangers and other employees were very helpful (as in "Sure, go ahead and use our compressor to air-up your tires. It's over there in the garage"). Bags of ice were plentiful and free. Yes, I said "free". They do, however, accept a donation as a thank-you for the ice. The bathrooms and showers were impeccable and, again, free. If you're not into tent camping they have a men's and a women's dorm. I didn't see the dorms myself, but a couple folks told me that, while spartan, they are very nice and clean.