I've mentioned this before, but too often people imagine that Los Angeles was the prototype of the modern American city, that it grew up around the automobile in the way that large sunbelt cities did. The truth is it was the first major city to grow up not around walking/horses but around streetcars. Yes, the automobile came soon afterwards, but it was really the streetcars that defined the basic city layout.
Here's a map from 1910 of the streetcar system.
Click through here and you can get one from 1949 before Judge Doom showed up.
...since the hamsters that power geocities are unhappy, click here for a small version of the 1949 map.