As a PV resident since 1947, I've seen a lot of stuff and can tell you the history behind Palos Verdes generally from a first-hand perspective. Here's one:
Did you know that there was once a prison roughly where Long's Drugs is now in the Peninsula Center? It was an "Honor Farm" (minimum security) and the prisoners worked on putting Crenshaw Blvd thru to PV Drive South . . . which, of course, was a proximate cause of the landslide. I'm not sure when it was opened (I was only born in 1947, after all), but it closed around 1955 when land movement began and work on Crenshaw ended. I don't recall much else in that valley during the early 1950's, but I was a kid and not taking notes. More on the history of the Slide later -- I remember when it started -- oh baby!