First there were two snakes curled up together... some kind of inter-species romance...
It was a little Red-bellied Snake, and a Garter Snake. I think the Garter was an Eastern Garter Snake, but it could possibly have been a Plains Garter Snake. (I'm sure realsarah will let me know fore sure...)
And then on the rocks near the parking lot I saw another Red-bellied snake and two more Garter Snakes.