Just got back from Memorial Day weekend houseboating on wonderful Trinity Lake, having flown into Trinity Center (O86) which is nice paved 3,000 foot plus airstrip right on the lake. The houseboating place (Cedar Stock) is only about 1/2 mile and they will pick you up although it did take a few minutes of convincing.
Houseboats rent early, but there is also the Trinity Center Inn right at one end of the runway and the Wyntoon resort nearby as well. In addition, there are numerous boat-in campgrounds so you could rent a ski-boat and camp.
The weather closed in on the last day, and I asked a local that was taking off for assistance in getting out. I followed her just below cloud level in the rain at 5,200 feet as we went down the lake and made a left turn over the mountains and into the upper Sacramento Valley, which I was very glad to see.
It should also be mentioned that this should be considered a mountain airport.