No problems with a 24 footer in Cottowood.
Remember it is a no generator campground and I would recommend taking your own drinking water in to the park. The Chisos Basin gets spring water pumped up from the desert. Cottonwood and Rio Grand Village have well water.
When we were campground host at the Chisos Basin CG from Apr-Aug 2014 we often had 24-28 foot Class C and Class A rigs in the CG.
Strongly recommend that you plan to stay in the first loop. Don't take the rig lower in the CG until you have walked. The second loop turn can be too tight for many rigs, and the bottom of the CG turn is too tight for a long wheelbase truck pulling an 18 foot trailer. I had to back the rig up the hill to the second loop before we could turn that guys rig around. (Yes, I had to back my 36 foot trailer uphill from the host site to the amphitheater parking lot to get out).
The entrance to the CG is very tight, unless you go a little past the entrance, turn left into the amphitheater parking lot and then straight into the CG.
Most of the campers were tents, but we were never without three or more truck campers, popups, teardrops, trailers, Class B, Class C or Class A rigs.
There was a contract awarded to rebuild the Chisos Basin CG dump station road area in Oct 2014. Google Maps image shows that work was completed.
The biggest rigs I say in the CG were a pair of 32 foot class C's. In sites 9 and 17. One was making a east to west cross country and the other was going the opposite direction. Both were rentals one with a family from Switzerland and the other from Denmark.
A couple additional points about Big Bend. There is almost no cell phone service in the park. Only a few locations. There is some WiFi at the Lodge in the Basin.
There are no showers in any of the campgrounds. There are four pay showers at the store in RGV. There are also a couple washers and dryers.
The park is very serious about not leaving out food, scented items like dishwashing soap, deodorant, etc. in the Chisos Basin the concern is to not attract bears. I had some campers whose tent was invaded by a fox one night. I saw a deer make a beeline across the CG one day to grab a bottle of lemon fresh Joy dishwashing soap.
At Cottonwood and RGV the concern is javelina. They will tear up a tent, ice chest or such to get at food.
Big Bend is an incredible, amazing place. Enjoy.
Full-Time 2014 - ????
“Not all who wander are lost.”
"You were supposed to turn back at the last street."
2012 Ram 2500 Mega Cab
2014 Flagstaff 832IKBS TT