Tent camping is allowed, but I don't know if you can spend the night there..
Yes, you absolutely can spend the night on the beach here, in a tent. They have an entire area on the beach for primitive camping. You should be able to purchase a camping permit at the front gate when you come in, but be warned that when we got here they had an "at capacity" sign up. So you may want to call and reserve ahead of time.
If I recall correctly tent camping is allowed overnight for a fee, and you don't need a permit when you have reservations at the State Park. The permit is for the other beaches, and can be purchased at the big gas station you pass coming into Mustang Island.
Yes. Yes.
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