I routinely see RVs parked overnight in those "sunrise to sunset" spots. I'm not advocating or recommending it but there are a whole lot of beach side parks in the area and, with it off season, I suspect the park officials aren't overly concerned about a night here and there.
Walmart (open 24 hours) allows RVs to park 2 nights free in the lot. The Nat'l and State Parks are open sunrise to sunset.
Yes there are several dispersed camping areas throughout the national park i might suggest the local richardson grove area and out hwy 36 there are some great areas pamplin grove is another good spot too
Humboldt and Del Norte counties have a lot of areas where you can pull off and camp. To gather that info your best bet is to stop in Arcata or Trinidad and talk to locals near the markets.
We usually sleep near a McDonald's as the Redwood National Park has no campsites. However the State Parks are more abundant and have camping. Not sure about cost.
Dispersed camping is available in Six Rivers National Forest an hour north near Gasquet. Wal-Mart in Crescent City 45 minutes north.
Side of the road places work fine. Just remember that Smokey the Bear works 9 to 5, so by 8am, rollup, repark and become a day use group. Hikers beware, there have been fatal California Cougar attacks. Prepare but don't worry. Just remember, they will go for the smallest or perceived weakest in your group. 3 or less need to be prepared for chasing off or facing down a hungry pair.
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