I came here 15 years ago with abalone-diving City friends. I'm not even sure that's a thing any more. Anyway, the campground is still here and it's still awesome. They have spots available when no one else does, and it's the simplest check-in ever: Pay them ($5 off for cash!), they give you a receipt for your windshield and tell you to park at any picnic table/fire ring that's not occupied. The rest of the world seems to get more complicated and bureaucratic, but this is the easiest damn check-in I've ever experienced. Checkout 2pm. Ocean Cove Bar and Grille is a sweaty uphill 3/4 mile walk away. Basic bar food, but great view of the ocean and campground.
funky little place, needs a LOT of maintenance, but their wifi was pretty good.. They have three private bathhouses: 1 - pleasantly warm, 2 - hot (> 100) 3 - very hot. (> 104) So if the one you want is in use you're outta luck until whoever's inside has had their fill. The pools seemed hotter to me - the medium seemed like 104 and the hot like 107-8 ... your mileage may vary.
What a cool discovery! You leave Route 160 just a little north of the bridge that takes you to Pittsburg/ Antioch and take a bumpy little road along the edge of Sherman Island. The road follows the southern side of the Sacramento River to the tip of the island, where there is a nice county park for the windsurfers. It's roughly where the Sac River meets the San Joaquin River, and it is a great windsurfing spot.
There is one big pool with a little waterfall, then up the hill are some bathtubs for your own private soak overlooking the wide valley. Really cool setup. Camping area is 200 yards down the hill. The pools are spectacular and the actual camping area is pleasant but rest of the property is extremely derelict. Walking up the crappy trail to the bathtubs in flip flops is hard for a 70-year old. It's pretty dangerous coming back down in wet flip-flops! Electric hookups and tent/van sleeping seem to be the same price.
Tub 1 seems to always be booked. Tubs 2 and 3 are the lower priced tubs most likely to be open. I did T2 because it looked cozier in the picture. I like it better I think, but in T3 you can kick back and look at the hills which is cool.