I discovered this route today...thought I'd seen all the East Bay had to offer. Nope. This one is of moderate difficulty, with lots of twisties, but the roads are good. The direction in which you take this route is very important, otherwise you'll miss the most spectacular scenery!

1.) Going east on I580, before the I580/I680 interchange in Dublin, take the Foothill Rd. exit and go south (right) into Pleasanton on Foothill Rd.

2.) After a couple of miles, when you see the golf links on the left, stop at the next stop sign and turn left. This is Castlewood Dr. (As I recall, there wasn't a street sign.)

3.) Continue on Castlewood and turn right onto the Pleasanton-Sunol Rd., which parallels the I680 freeway.

4.) At the 4-way stop in Sunol, turn left onto Paloma Rd. This turns into Calaveras Rd. 

5.) Continue on Calaveras up into the mountains and enjoy the spectacular views of the Calaveras Reservoir and broad country vistas. This is the Sunol/Ohlone Regional Wilderness area. The road becomes one lane at times, but is a wide one lane.

6.) At Felter Rd. (where the road "T's" at a stop sign) TURN LEFT. Continue on Felter and be prepared for some absolutely stunning vistas of the Santa Clara valley and San Jose! Be sure you do this on a clear day. Again, at times the road is just one lane.

7.) After a couple of miles, Felter turns into Sierra Rd. Continue on Sierra down the mountain and into the city (Milpitas, I believe).

8.) At Piedmont (there is a traffic light), turn right. Then, at Calaveras Rd., turn right. After a mile or two, note that Calaveras becomes Felter Rd., so you must now turn left onto Calaveras, retracing your route along the Calaveras Lake. (If you stay on Felter, you'd be making an endless loop.)

The loop is about 70 miles, starting at the Foothill Rd exit off of I580. It took me two-and-one-half hours to complete. (There is another road off of Felter that also has possibilities...Marsh Rd./Day Rd., but I didn't try that route today.) I'll definitely be doing this one again!