It's located on FM 3404 that runs from Kingsland west to Rte. 71. I've only been to the place twice, and the really remarkable thing is the number of xenoliths there. Other than that it's a fairly typical example of a coarse-grained porphyritic (Town Mountain) granite from the Llano Uplift. It's also a fairly typical example of what we call in Texas "a low-water crossing." There should also be some interesting pieces of the various rock types of the Llano Uplift in the river bed.
That's what it looks like, upriver is to the right. I take no responsibility for any parking trouble that you get into. Too far out into that sand and your car could sink in to the axles. And don't call me for help if that happens, I am NOT a sedimentologist, I don't do sand. Call me when it lithifies.
Technically, the state only owns the river bed and the road right-of-way, so be careful about trespassing.
And this would be the reason to go there. The xenoliths are pieces of amphibolite. In some cases the granitic material has invaded the xenoliths along foliation. By the way, those aren't my feet, so the xenoliths aren't quite as big as you were thinking.
Extreme close-up of that area.
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