Yes there are several parks along the highway. Up till salt point. Most have big enough campsites for a 28ft trailer. If you're concerned about the road perhaps stay at the Dunes which is the first Park in the Sonoma coast. That's right out of Bodega Bay. I believe they can accommodate all sorts of trailers. They have showers and a dump station.
I am not sure about that. I don't know if the road can handle 28 foot trailers....
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