I had some time to spare and my bike in the back of my car in midtown L.A. The nearest location being Runyon Canyon.

In theory, there is a place to ride. In practice, it’s one road. Basically, go through the gate up the road and look for the well-worn left turn.
It’s not a mountain bike ride. It’s a short out and back on a busy single road.

I would strongly recommend the road to the road riders out there looking for something a little different pretty early in the day. The road is smooth enough to climb without worrying about your equipment. It spills out to Mulholland, so you get a nice car-free (steep!) climb to Mulholland, then pick your favorite descent home. For those of you wondering what climbing some European roads is like, this is a short example.