Los Trancos OSP is a tiny little preserve, just 274 acres big but it’s packed with trails and is a real gem of a place to go for a short wander after work. I spent about 2 hours in the preserve and walked nearly every trail, some segments twice. From the intersection of 280 and Page Mill it’s a short 15 minute drive to the parking lot, right across form the main Montebello OSP parking lot. The preserve gets very little use during the week so it’s a great place for a little quiet time on the way home. Most people know this preserve for the educational Fault trail that imparts information about earthquakes and fault lines. The best trails in the park, however skip this segment and offer a very pleasant ramble through an old oak wood.
About the hike: Pick up a map of the preserve from the trailhead and spend a bit of time studying the preserve. You’re realize that this a trail dense environment. You’ll need to watch the turning carefully but the good news is that the park is small enough that even if you take the wrong turn you’ll figure it out quickly and likely end up back where you started with little effort. Start your hike from the sign board at the trailhead and follow the signs for the Franciscan Loop trail (Ignore the fault Trail for now). Follow Franciscan Loop down into the forest, across a bridge and bear to the left at the next two intersections, turning onto the Lost Creek Loop trail.
Lost Creek Loop goes downhill a bit and then when it starts to climb you’ll see an intersection with the Page Mill Trail off to your left. There’ll probably be a barricade across this trail saying that it’s closed. As near as I can tell that trail hasn’t been open in 10 years, the barricade has been there every time I’ve been in the preserve, summer, winter or spring. Just past this intersection with Page Mill Trail there’s a second intersection on your right going uphill, that’s the continuation of the Lost Creek Loop, turn here and go uphill until you rejoin Franciscan Loop. Bear left on Franciscan Loop a short ways and you’ll come to an intersection that would take you back to your car if you turned right. Go straight instead towards the Page Mill Trail (this section is open) and turn left onto Page Mill Trail.
Follow the Page Mill trail along an old road cut down to a small gate at the boundary of the preserve. Just before you reach the gate you’ll see a little singletrack on your left, follow this trail downhill and you’ll end up back at an intersection you’ve been at before, where Lost Creek Loop meets Page Mill trail. Turn left and walk this portion of Lost Creek Loop again, it’s pretty and deserves a second look. Go uphill until you rejoin Franciscan Loop and bear left on Franciscan Loop again. This time when you come to the intersection that heads uphill to the parking area go right and follow the trail up to the intersection of the fault trail.
Turn right onto the Fault Trail and walk to 1.5 mile loop, stopping to look at the numbered signposts and read about them on the map that you should have picked up at the trailhead. The loop will bring you back to the trail to your car. On your way uphill there’s a small unmarked braid on your right, take that trail, it’s the very first part of the fault trail that we skipped on the way into the preserve. Admire the views from the top of this trail as it looks over the Bay. You’ll end the hike back at your car having walked a bit more than 5 miles.
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