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"Thomas Guide." Wikipedia, The Free Encyclopedia. 13 Feb 2008, 07:44 UTC. Wikimedia Foundation, Inc. 3 Apr 2008
Thomas Guide is the title of a series of paperback, spiral-bound atlases featuring detailed street maps of various large metropolitan areas in the United States, in the metro areas of Boise, Las Vegas, Los Angeles, Oakland, Phoenix, Portland, Reno-Tahoe, Sacramento, Salem, San Francisco, Seattle, Spokane, Tucson, and Washington, D.C.. Road Atlas titles are Arizona including Las Vegas, California Including portions of Nevada, and Pacific Northwest covering Washington, Oregon, Western Idaho, Southwestern British Columbia. The map books are usually arranged by county; for example, separate Thomas Guides have been published for Los Angeles County and San Diego County. There are also guides that will have two or three counties combined (for example, Los Angeles and Orange County), or guides that cover a metropolitan area (for instance, the San Francisco Bay Area). Each guide has a detailed index of streets and points of interest, as well as arterial maps for easy page location..
Thomas Bros. Maps, the publishers of the Thomas Guide, was started in Oakland, California in 1915 by cartographer George Coupland Thomas and his two brothers, who were business partners. The company relocated its headquarters to Los Angeles in 1940, and to suburban Irvine, California in the 1950s. George Coupland Thomas died in 1955 and the ownership of the company was transferred to his widow and the Thomas family. The company remained privately owned until it was purchased by and became a wholly owned subsidiary of Rand McNally & Co. in 1999. Updated editions are released annually. Folding map products are created as a derivative of the Thomas Guides, which carry the Rand McNally name, but mention that the content is from the Thomas Guides. Rand McNally also releases Thomas Guide-like Street Guides and traditional fold-out versions of maps covering regions of North America not covered by the Thomas Guides.
Thomas Guide atlases are often referred to colloquially as a Thomas Brothers (for Thomas Bros. Maps). They are so commonly used in Southern California that governments, businesses, individuals and even emergency response agencies will often refer to the page number and map grid to help specify a location.
Businesses often use the large Thomas Guide wall maps. One common use for the wall maps is for delivery businesses, such as a local pizza restaurant. In addition, custom versions of the guides and wall maps are produced for businesses and governments that include such things as census tracts, locations of government facilities, watershed boundaries, and political boundaries.
There are also CD-ROM digital editions of the Thomas Guide atlases available (Microsoft Windows only). In addition, the Thomas Brothers digital database can be licensed to companies and governments to use as a base map for geographical information systems applications
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