After hiking into the Cobblestone Mountain Quadrangle with Let's Fly to hide some caches, we spotted a couple of places for more caches on the hike back to the car. This was back when the gate that is just past the last picnic area on the lake was closed most of the time.
The name used to tell you what you are looking for, but that no longer applies. It is now a pill bottle. And the name now tells you *exactly* where to look... well, behind it. Logsheet only, so bring a pencil.
As noted, the terrain rating was set back when this road was closed to vehicles. We see no reason to change it, now, after more than 50 Finds.
There is no longer any entry fee to the Lake Piru Recreation Area, as long as you tell the person at the entrance shack that you want to drive to the Pothole Trail parking area, which is in USFS territory. Once you get past the last parking area for the lake, the road can be pretty chewed-up in places, but it is still drivable by any vehicle.
Good luck! Have fun 