Last night I decided to go explore some an area of Purisima Creek that I’ve never gone to before, the Irish Ridge Trail. The hike ended up being a 6 mile hike with lots of descending and climbing and more opportunities for further exploration in the future. In retrospect I wish I had held off until a weekend because now I want to go back and explore the rest of this area but it was still a very lovely hike and well worth a try if you haven’t gone there before, even if it is an out and back. I should note, however, that if you’ve read my other hike descriptions you’ve probably figured out that I tend to hike solo. This area was one of the few areas of the San Francisco Peninsula that I actually thought that was a bad idea, the Irish Ridge area appears to get almost zero usage and it’s deep in the nowhere. If you fall or injure yourself in this part of the park you cannot rely on someone finding you and coming to your aid so take a friend on this walk.
About the park: I’ve described Purisima previously so I won’t spend more time describing the park. I parked at the PC04 gate off Tunitas Creek Road. To get here take Skyline Drive to the intersection with Kings Mountain Road and Tunitas Creek. Turn westerly onto Tunitas Creek and slow down. This is a twisty and bumpy road. Follow this road for about a mile or so and you’ll come to an intersection with Swett Road, stay to the left and continue on Tunitas Creek for another couple miles until you see the brown and yellow gate for PC04 on your right. There’s no developed parking here but there are lots of roadside pullouts you can park in. Also bear in mind that there are no bathrooms or water on this side of the park so be prepared.
About the hike: From PC04, walk down The Grabtown Gulch trail 0.3 miles and then turn left onto the Borden Hatch Mill Trail. Follow BHMT for 0.2 miles and turn onto the Bald Knob Trail. Follow the lovely Bald Knob singletrack for 1.3 miles to a 4-way intersection and take a sharp left turn onto Irish Ridge Trail. I’m not certain but I would suspect that this ridge is named for Milton Irish, who operated a sawmill over in El Corte de Madera Creek OSP back in the late 1800s and this area has a heavy logging history.
You will descend steeply on Irish Ridge Trail for the first 100 yards or so and you’ll be tempted to turn around but continue on for a bit and the trail begins to descend more gradually. You’ll hit one section which has some stunning views of the southcoast, especially if the fog should be out. Continue on this trail and you’ll note that the trail becomes rougher and shows little sign of recent use. In places there are branches of poison oak reaching out over the trail so be cautious about touching the plant life. This trail also has lots of coyote and scat and similar evidence of other critters, testifying to the scarcity of use in this part of the park.
Continue down Irish Ridge to the end of the trail or to the intersection with Lobitos Creek Trail. You’ll have descended about 500 feet in total if I’m reading this here topo map correctly. Lobitos Creek appears to be a 2 mile long ramble through the redwoods, a welcome relief after the open ridge trail you just descended on. I’ll be coming back to check out Lobitos Creek another time when evening is not approaching rapidly. But even if you’re turning around, walk down the first 50 yards of Lobitos Creek and check out the huge redwood tree just to the left of the trail with the very funky branch arcing over the trail. I’ve never seen a redwood growing like this one, it’s quite cool and worth a look while you’re in the neighborhood.
Now, unfortunately, it’s time to turn around and head back up the hill. It’s not too steep until you hit those last 100 yards or so and it’s a pleasant ramble back the way you came on Bald Knob to Borden Hatch to Grabtown Gulch to PC04. According to the map this route was just about exactly 6 miles. If you do Lobitos Creek it would be 10 in total. I did the hike in exactly 2 hours but I was really pushing and wished I could take it slower but I had gotten a late start leaving from work and it was getting dark by the time I walked out. Plan that it’ll take you 2.5 -3 hours at a comfortable pace with time for a snack at one or more points along the trail.