A friend of mine has property in Leakey, Texas, that she said I can camp on. She and her siblings will eventual put a cabin/ house up there for their use. Right now, it has no water and no electricity, so they have no intention of using it any time soon.
It's a 5-hour drive to Leakey. If I leave after lunch on Sunday, it will be too dark when I arrive, so I'll just drive the three hours to San Marcos and stay somewhere.
It's 2.5 hours from San Marcos to Leakey. I'll be able to find the spot. (So far I only have the coordinates: 29°41'28.3"N 99°43'51.5"W. Google Maps says that's 685 David Rankin Rd, Rio Frio, Texas.)
And then it's only 15 mins to Garner State Park.
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The Old Baldy, Foshee, Bridges, and Crystal Cave Loop is recommended for seeing everything.
The Old Baldy trail is only a mile, but it's supposed to have some pretty steep rough areas, so I'll hike that on Day One by itself.
I should be able to do both of these on Day Two.
Frio Canyon Trail is 3.3 level miles, so it will be pretty easy.
Wild Horse Creek, Highway, and Campos Trail Loop is also 3.3 miles.
All of these will be enough for two days, and I will head home Wednesday morning.
Garner State Park