First off I should say that due to the Clayton fire (over the hill to the E from NV in Lake County now 95% contained, there may be higher than usual occupancy in camping/rv locations in Sonoma, Napa and Solano counties. IMO plan ahead.
I‘m kinda of partial to Sonoma County as I lived on the Sonoma coast for 20 years. However I remember as a child when our family who lived in Concord would picnic for the day in NV and it was Krug, Beringer and Christina Brothers with tasting room open and fruit meant walnuts and plums, not grapes. The rest is history. Both Sonoma and Napa Valleys are gorgeous and world renown for their wines. I simply like Sonoma more as the crowds are smaller. For those who live in the area IMO there are no valley boundaries, just a good bottle shop or better yet, a good winery connection! Note, allow extra hours when turning left onto Hwy29/128 in NV on weekends and this time of the year (with the crush on) probably any day thru October.
Seems the NorCal WBCCI meets at Cassini Ranch (Duncan’s Mills/116) on the Russian River, Wrights Beach on Hwy 1 a few miles S of the 116/1 intersection is on the beach awesome
. There are also some camping and RV’s opportunities in the Bodega Bay area.
For Sonoma County try http://www.sonomacounty.com/campgrounds
and click on show more results at the bottom. Note the Sonoma County fairgrounds in Santa Rosa is listed and a great central location (in Hwy 12 just E of 101) to head N to Dry Creek/Alex Val/ 101or S to Valley of the Moon/Sonoma town.
Don’t ignore the Sonoma Coast as the drive to Guerneville on 116 and left onto Westside road to Dry Creek/Healdsburg or Hwy 1 S thru Bodega Bay to Petaluma and on to the Carneros region is reasonable for a day trip…and on to Sonoma, and on to Napa/29 if you’re interested. In NV, stick to the Silverado trail for the N/S driving if you can using the crossroads to access the west side.
Note check the schedule for Infineon Raceway @ Sears Point in case they are have a NASCAR or other event. It affects the traffic in the whole N Bay.
As for Napa Bothe SP
is in NV itself and hard to beat the location mid-way between St Helena and Calistoga on 29/128.
If you have trouble finding reservations, consider Solano County (Cordelia/Suisun on I/80) for RV parks as it’s a very short drive to Napa Town via American Canyon and access N to Hwy29 and the Silverado Trail.
Lastly and please don’t consider this a hijack but two stops in Santa Rosa are worthy of your time. I mean, you can only wine taste sooo long! The first is the Charles Schultz Museum (see pic below, obviously) and the second is the Luther Burbank Home and Gardens both in Santa Rosa. Luther, thank forever for those Santa Rosa plums!