What? : Small Preserve on the side of hwy 35 just below the closed viewing point. The trail is going all the way down to the creek.
Where? : From the junction of Page Mill road and hwy 35 take north on hwy 35 for 1.2-miles, pass the close viewing point on your right and park on the left (west) side of the road. This is good parking place to visit Russian Ridge and for sunset viewing.
Due note: The park is popular by mountain bikes.
My thoughts: This is not recommended park to visit. Compare to all other attractive parks this area has to offer Coal Creek Preserve has few hiking options, trail is going down to the creek below and then you need to climb all the way back to the ridge.
Overall, I hiked 5.7 miles -/+ 1,300f, all the way down to the creek below, Alpine Road Trailhead, and climb up back to the parking lot.
The trail starts right at the viewing point, it connects to the private road below, keep go down to the end of the road. From here the trail start.
Keep going straight at the first junction (we will be back from the left) and after additional 0.5 mile you will reach the main park Alpine trail. Turn left and hike 1.7 miles all the way down to lower Alpine Road Trailhead.
From here you need to climb up. Turn right up on Cloud Rest Trail and hike to the top of the hill. The open grassland hill has nice view of the bay area below. From the hill another 1 mile will take you back to your car on hwy 35.
Another hiking option (Blue) is to start at skyline highway 0.6 mile north of Silicon Valley Vista Point.
Park your car on the slide of the road that take Crazy Petes Rd. down, after short hike you will reach the close small parking-lot, from here you are getting into the reservation. The trail will keep descending down and after 0.4 mile from the skyline road you will reach trail junction, take the left fork.
After 0.7 miles the trail will reconnect, turn right and keep descending, after short hike you will reach to the small waterfall with bridge, few hundred feet later you will reach the main park trail.
From this point climb up the ridge, at the fork take the right and hike all the way up to the place you parked your car.