If you are in Guerneville then definitely hire a canoe at Burkes (on the River road towards Forestville). This is a great way to see the Russian river and it's wildlife and a fantastic way to cool off in the summer. Canoes are relatively cheap ($59 for each canoe - you can get about 3 adults in each canoe) and they pick you up at the designated drop off area, 3.5 hours down the river near Guerneville. It's a lovely way to spend the day in the area, just make sure you pick up the canoe before 12pm and that you bring your own lunch, water and swimming gear.