[Those Who Squirm!]

Originally Posted by CityBoyDoug

ER....good question. Before ZIP codes, LA was divided into Zones. Each Zone had a number. Of course the Zones are now gone and have been replaced with ZIP codes.

I've noticed that the old zone numbers usually correspond to the fourth and fifth digits of the present ZIP code. Today the full zip code for 9220 S. Broadway is 90003-4042. I imagine it was the same for other cities. The postal service had already been using the zone numbers and merely prefixed a three-digit designation for each city.