Well it wasn't really secret anyway. That's why there were tracks and roads up there. Trash dumpers found it about a year ago. So eventually the owner put up heavy gates at the entrances and cleaned it up. There was a way in for a few days when I got that photo but it was difficult. When my son built his gambler car we tested it up there. We hauled a few bags full of trash down, but it didn't make a dent. There are no longer any ways in that don't involve destruction of property. It's unlikely to be vehicle accessible ever again. The trash dumpers ruined it for everyone.
California is just as SUV/truck crazy as anywhere else. From the teeming masses of all-look-the-same crossovers to pickups, suburbans, rivians, raptors, hummers, cyberslabs, porsches, lambos, lowered, lifted, lowriders, vintage, pinstriped, clapped out beaters with 10' wood bed walls full of cardboard, and drift trucks that pour all their tire smoke out of the bed.
