We stayed the weekend at the KOA up between Healdsburg and Cloverdale. The kids enjoyed the pool and biking around the campground. If you go there Google maps had the road incorrectly named Koe Road when it should be Asti Ridge Road or KOA Road.
Geysers Road is a long and remote ride, carry basic tools and some extra water. Here's a map of the route.
There's plenty of other descriptions of The Geysers loop out there, but there's a couple things I did not remember reading before I rode.
First is that Geysers Road includes gravel sections. You hit the first patch just after the turnoff for Pine Flat, and I thought for a bit that I must be on the wrong road. The first stretch is one of the longest, the rest range from about 100 to 300 yards. There's maybe 6 to 10 gravel sections on the route up from Cloverdale to Geysers Resort Road and 2 or 3 of them on the way from there back to Healdsburg. There did not seem to be rhyme or reason for them, some were downhill, a couple uphill, and others flat. A couple butted up against some pretty darn good pavement that would go for 1/3 mile before returning to the rougher old surface. At least all of them had a "Loose Gravel" warning sign. The only reference I could find was to regular seismic activity causing cracked roads, perhaps the gravel is where faults cross a road?
It seemed like Geysers Road has more than it's share of cattle grates, especially on the way down. You can't miss them. Unfortunately.
The last thing to note was the lack of options for water once I returned to the valley. There was a general store on Alexander Valley Road about a mile or two after the 128 intersection, and there's a campground where the road crosses the river that could have water. Didn't see anything other than wine tasting options until another general store at the corner of Lambert Bridge Road. Probably should have continued into Healdsburg for refreshments then taken Dry Creek to Lamber Bridge Road, or Westside Road to West Dry Creek.
The riding was good in the morning, with some great scenery along the creek riding up from Cloverdale. It looked like you could get to the river for a swim where the bridge crosses the road about 10 miles up. The grade is a bit steeper after the bridge, but still very manageable. I was able to stay mostly in the shade by using the full road.
The road ramps right up after the right turn at Geysers Resort Road. Get in a good gear because it's about 1 1/2 miles of mostly exposed steeps before it eases up significantly. There were a couple of spots where you can catch your breath, but not many. The road continues up on a mellow grade for a mile or two before a gated fire-road climbs up to Geyser Peak on your right at around 2,650 feet elevation, then there's a long downhill followed by a moderate climb.
After the run down from the hills and across the sun-baked valley West Dry Creek Road offered some welcome shade. There's a "No Outlet" sign at the intersection with Joachim Bridge Road. I'd wager the sign is wrong but I was late getting back to the campground and couldn't afford to double back at a dead end so I headed back over to Dry Creek Road.
The chateaus and villas were beautiful but it all felt rather exclusive and oriented to one type of visitor. Also was hard to stop thinking of all the people tasting their wine and then getting back behind the wheel of their cars. I liked the Geysers Road climbing alright, but was not so fond of riding in the valley.