The end of the loop trail is impassable in years of heavy rain because of flooding from the Russian River. You have a choice of an out & back on either arm of the trail. Both arms offer side trails down to the lake frequently used by people fishing there. Crowded on weekends & holidays. At the end of the stem trail from the parking lot to Lake Benoist, turn left for a walk with more scenic views & redwoods, & CA Bay trees on the uphill side. There is a Great Blue Heron rookery there at the right time of year. If, instead, you turn right at the fork you will walk between the lake & the Russian River. This sunnier side offers side trails down to shaded spots along the river. WARNING: Highly recommend you tuck your pants into your socks here, especially on this side, during tick season. Most ticks I've encountered on the main trails of this park are not the species that carries Lyme Disease. A less traveled short trail goes up & over the hillside from the stem trail and loops back to the small redwood grove beside the parking lot. The slope up the trail from the stem is steep. It is easier to start at the redwood grove, but the trailhead may be harder to find there your first time. The grove itself is a cool summer respite. Many nice picnic table areas, but expect crowds & the noise of a volleyball game on weekends & holidays. Dogs are permitted on leash at this & most other Sonoma County Regional Parks, in contrast to the dog unfriendly state parks in the area.