Among the landmarks in this screen shot are Stoney Point on the far right and some of the rocks at or near the Iverson Movie Ranch in the center background, which would be right where the 118 freeway now crosses Topanga. All the way in the background is Oat Mountain.
Here's a more recent shot of Stoney Point, which is a familiar sight to motorists traveling along the northern end of Topanga. It's a popular rock-climbing venue these days. It has minimal history as a movie location in its own right, but it appears frequently in the background of films shot at the nearby Iverson Movie Ranch.
The Grapes of Wrath" (1940), seen above. In the movie itself, Stoney Point was cut out of the shot, with the focus instead on the rich farmland that surrounded it in 1940 — all of which has since been fully developed into residential and business properties. Check out Jerry England's blog for a good entry on Stoney Point, including a bit more about "Grapes of Wrath."
Here's an example of how this shot is handled in the movie:
The Real McCoys" offers another perspective, even if it's a lot lighter in tone.