The Hike:

Wind through the corrall, following an old ranch road up Long Canyon. The route is fairly obvious, as it is the path of least resistance up the canyon. You will stay in the canyon the entire way up to the top of the watershed. Once you reach the top of the canyon, turn left and follow the trail above an old pond. Keep following the trail, and it will loop back toward the trailhead. When you see the trail turn left back into Long Canyon, follow it. This will take you back to the trail within the canyon and back to your car.

Distance: The entire loop is about 9.5 to 10 miles, so be prepared to spend some time out here! Elevation gain is about 1000 feet over the first 3 miles, so it is real gradual if you do the loop by going up the canyon first.

How to get there: 

From Yolo County, take Highway 128 toward Lake Berryessa.  Turn right at the 128/121 intersection, staying on 128.  At the Turtle Rock bar, turn right again onto Berryessa/Knoxville road.  Continue on Berryessa/Knoxville, past the lake, over both Pope Creek and Putah Creek bridges at the North end of the lake, and up into the mountains beyond.  The road will narrow, roughen, and wind up into the canyon until you reach the parking on the side of the road at mile marker 28.  There are 8 concrete low-water crossings on Knoxville road, prior to the parking. Parking is available at an old corrall on the right side of the road. You can't miss it, and I have an image of the parking area below.