These are pictures and a video from the "Satwiwa Loop and Upper Cabin Trail" (link) on the western edge of the Santa Monica Mountains. The first part of the trail - the Old Cabin Trail - is a joggable Class 1 trail. That trail ends at the remains of the old cabin and the Danielson monument, which commemorates the man whose land became part of Point Mugu State Park and the neighboring NPS property.
The Tarzana area of Los Angeles hosts a geological feature known as the Vanalden "Cave". I'd heard about it but never bothered to visit until now. Getting to it was OK, even if the "cave" wasn't. And, yes, I'm going to keep up the scare quotes.
I knew going in that the "cave" wasn't much and that it was defaced with graffiti, but I was even more disappointed when I got there. It's basically an overhang with a few holes in it, and it's impossible to get a picture that doesn't have spray paint in it.