I camped at several of these parks when I was a Scoutmaster of our local Boy Scout Troop. There is no camping at Fort McKavett, they did allow our Boy Scout troop to spend the night in the old Calvary barracks and use the cowboy showers. The caverns are beautiful about a 2 mile hike and warm. Our scouts loved swimming in Lake Balmorhea. We did not stay at Davis Mountains State Park, we stay at the BSA Buffalo Trails Scout Ranch, but some of our scouts did go over for and evening tour and star watching to earn there merit badges
South Llano State Park – Neat, Clean lots of wildlife, great place to float the river.
1927 Park Road 73
Junction, TX 76849
(325) 446-3994
https://tpwd.texas.gov/state-parks/south-llano-river
Fort McKavett State Historic Site – Great place to visit, No Camping
About 45 minutes from South Llano State Park
7066 FM 864
Fort McKavett, TX 76841
325-396-2358
Fort McKavett State Historic Site | Fort McKavett, Texas | Texas Historical Commission
Caverns of Sonora
About 1 Hour from Fort McKavett
RR 1989 @ I-H10 Exit 392
Caverns of Sonora Rd.
1711 PR 4468
Sonora, Texas 76950
Phone: (325) 387-3105 or (325) 387-6507
Contact Us :: Caverns of Sonora
Balmorhea State Park
About 3 Hours from Sonora
9207 TX-17
Toyahvale, TX 79786
(432) 375-2370
https://tpwd.texas.gov/state-parks/balmorhea
Davis Mountains State Park
About 35 minutes south of Lake Balmorhea
P.O. Box 1707
Fort Davis, TX 79734
(432) 426-3337
https://tpwd.texas.gov/state-parks/davis-mountains
From there you can head 1 hour south to:
Big Bend National Park, heard it’s a great place
TX 79834-0129
(432) 477-2251
https://www.nps.gov/bibe/index.htm
And maybe stop and spend a night hoping to see the Marfa lights?
Marfa, TX
Visit Marfa, Texas