It is a relatively small park, no long trails out there.
Not sure if they allow horses but call ahead of time
I didn't see any facilities for horses on my last visit. Right now, no lodging or camping is available until 2019 due to renovations
They barely allowed our dogs anywhere there, but I do know Big Bend State park allows horse back riding! We did that a few years ago, and it's not too far.
They are not on the list of State parks that allow horseback riding. (tpwd.Texas.gov/state-parks/parks/things-to-do/equestrian) You may want to call to verify.
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