If you have lived in Phoenix any length of time you know that the city is laid out in a grid. Squares of 1 mile. Major streets (or major thorough-ways) run every mile in each cardinal direction. Minor streets every mile in between.
If you know anything about Baselines and Meridians than you basically have the makeup or layout of the Valley. The Arizona baseline is Baseline Road and runs west/east. Avenues and Streets run north/south. Streets are east of Central (east side) and Avenues are west of Central (west side). Major roads running west/east have a name (not a number). This is not so for roads running north/south although there are a few exceptions. Most roads running north/south are a street number (east side) or avenue number (west side).
Addresses have a pattern as well. Even numbered addresses are found on the north side and west side of a road. Odd numbered addresses are found on the south and east side of the road.
Zip codes have their pattern as well. Zip codes that start with 850 are City of Phoenix. Zip codes that start with 852 are east side cities. Zip codes that start with 853 are west side cities. There are two exceptions: 85331 and 85377 are north east. I do not know why!
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