The Thomas Guide is a detailed, full-color printed street map and atlas that helps people navigate metropolitan areas. Tools such as GPS and Google Maps have taken over a lot of Thomas Guide territory for most travelers, but these spiral-bound guides still have a place when you need detailed street maps in unfamiliar cities. The Thomas Guide is particularly popular in Southern California, and considered indispensable in places like Los Angeles.
Thomas Guide Layout
Each page of the Thomas Guide covers a unique geographical area. Specific neighborhoods, communities and streets each get their own page. This might create some confusion because the pages don't necessarily go in sequential order or even start on Page 1. When looking up a location, you need to match it with the unique page number. Each map is divided into grids that represent a half-mile square, and these areas are marked using grid coordinates of A1 to J7.
Finding a Location
Select the Thomas Guide that covers your county. Check the Street Index for the address you need. In larger areas, there might be more than one listing, so match up the city or the ZIP code. You'll see a page number that contains the map you need as well as grid coordinates that tell you how to find that address on the map. The columns are in letters and the rows are in numbers. For example, your listing might say Page 875 B-3. Flip to page 875 and follow Column B until it intersects with Row 3.