» Official Trail Map: Good map showing various hiking trails. Contour information and mileage of individual sections is missing.
» Redwood Hikes Map: Annotated trail map of San Lorenzo Valley that shows many parks, not just Henry Cowell. This is an excellent map sold by Dave Baselt ($6.95 in Jan 2012).
Trail Maps: The route has innumerable junctions, some of which are unmarked. So textual directions below are not sufficient. Having a good trail map is important. I found the Redwood Hikes Map for San Lorenzo Valley very useful. It has clearly marked trails and intersections.
To Henry Cowell Redwoods (4.1 miles): From the Buckeye Picnic Area in Harvey West Park, follow an unnamed trail (0.4 miles) that goes next to a creek and meanders high up amid the hills overlooking Harvey West Park. The trail descends back down to the park. Turn left and follow unnamed trails (0.4 miles) towards Pogonip Preserve. Follow Harvey West Trail (0.3 miles) → Lookout Loop Trail (0.2 miles) → Pogonip Creek Nature Loop (0.2 miles) to reach a paved road. Follow Pogonip Creek Nature Loop (0.3 miles) parallel to the road → Prairie Trail (0.2 miles) → left on Brayshaw Trail (0.2 miles) → right on Ohlone Trail (0.3 miles) → left on Fern Trail (0.9 miles) → Rincon Trail (0.3 miles) to reach an entrance for Pogonip Preserve along Highway 9. Turn left and follow Rincon Connector Trail (0.4 miles) to reach Highway 9. Cross the highway and enter Henry Cowell Redwoods.
River Crossings in Henry Cowell Redwoods (3.0 miles): From Highway 9, follow an unnamed trail (0.1 miles) → right on Rincon Fire Road (0.7 miles) to reach an intersection with Diversion Dam Trail. This is where we turned right to follow Rincon Fire Road, a sandy trail that quickly reaches San Lorenzo River. Prior to this intersection, there are many points where the river may be accessed. However, none of them is the right spot for the river crossing.
First river crossing: The first river crossing was easy in September 2012, when water level was fairly low. A series of stones had been placed in the shape of an arch to make the crossing easier. After crossing the river, follow Rincon Fire Road (0.5 miles) → left on Diversion Dam Trail (0.3 miles) to reach the second river crosssing.
Second river crossing: The second river crossing was tricky because the river is deep at various points. However, there are several rocks in the riverbed that we hopped over to reach the other bank. There was no trail on the other side. After climbing up about 30 to 40 feet, we discovered an unmaintained, unmarked Diversion Dam Trail. We followed Diversion Dam Trail (0.6 miles) to reach the the interesection with Rincon Fire Road (where we had earlier turned right for the first river crossing). We continued along Rincon Fire Road (0.7 miles) to reach a parking lot for Henry Cowell on Highway 9. Just before the parking lot, there is a trail going left. We followed this unnamed trail (0.1 miles) to reach another point along Highway 9. Right across the road lies an entrance into Pogonip Preserve.
Through Pogonip Preserve to Harvey West Parking Lot (3.3 miles): Follow Rincon Connector Trail (0.3 miles) to reach another park entrance for Pogonip Preserve on Highway 9. Then follow Rincon Trail (0.3 miles) → Limekiln Trail (0.5 miles) → Limekiln Trail (0.3 miles) to reach a five-way intersection. Follow Spring Trail (0.7 miles) → Lookout Trail (0.4 miles) → right on Harvey West Trail (0.3 miles) → walk through Harvey West Park (0.5 miles) to reach the parking lot near Buckeye Picnic Area.