We purchased these cool inner tubes. They were fully equipped with a cooler, backrest, cup holders and extra storage. We were the coolest and only group on the river.

Floating down the river during the week to avoid the weekend crowds is best. We did see a few kayaks pass by, but for the most part we had the river all to ourselves.
We took a lunch break on a small beach along the river, and I found this cool hammock to rest on.
As you can see I was very relaxed.
A few days before exploring the river we visited a winery, Fort Ross, and did some short hikes. Here are just a few pics of the adventure.
Castello di Amorosa winery
The Sonoma Coast State Beach Russian Gulch.
An unexpected wave got me drenched!.