A great escape from Silicon Valley is to head up into the Santa Cruz Mountains in a relaxing loop from the redwoods to the ocean and back. Give yourself at least three hours, as you'll rarely be able to drive over 30 mph on these twisting mountain roads.
On the map, look for State Highway 84 running west of I-280. One basic route takes Highway 84 west through Woodside and up a very curvy section to the intersection with Highway 35 (Alice's Restaurant at this junction is a popular pit stop). Cross Highway 35 and take Highway 84 through La Honda and on to its intersection with Highway 1 at San Gregorio.
Head south till you see a sign pointing to Pescadro, then turn left onto Pescadero Creek Road. Continue on Pescadero Creek Road as it climbs back up into the redwoods and passes through San Mateo County Memorial Park. A few miles up the road you'll hit an intersection with Alpine Road -- you can turn right here for a wider loop or turn left and go back to Highway 84, where you can turn right and go back the way you came.
Alpine Road is very narrow at first -- the redwoods feel fender-kissing close -- and very curvy all the way back up to Highway 35. Again, loop options abound (Highway 35 is a lovely route in its own right), but the easiest move is to cross Highway 35 and take Page Mill Road back to Interstate 280 (another very twisty route -- watch for bicyclists around every turn.
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