Rand McNally Radio Map of the United States

Fabulous radio map of the United States published just a few years after the nation’s first commercial broadcast!

On November 20th, 1920, the Westinghouse Electric and Manufacturing Company of Pittsburgh PA, operating under callsign KDKA, made history as the first commercial radio broadcast when they released the results of the Harding-Cox presidential election over the airwaves. WWJ in Detroit followed later that year, but it wouldn’t be until 1926 that the first radio network, the National Broadcasting Corporation, was organized under the parent company Radio Corporation of America.

This map of the United States was published in Chicago by Rand McNally, probably in 1923 according to the date code in the lower right corner (8 R 23). It shows just how popular the media had become in the first few years of the 1920s, listing over 800 different stations at the bottom of the page, organized alphabetically by call sign. Many of these broadcasting stations are identified geographically on the map, in addition to radio districts, time zones, and divisions of the American Radio Relay League.

A comprehensive index of radio stations in the United States and Canada can be found on the verso, listing the operator, state, call signal, wavelength, station location, and service (private, public, radio compass, government, etc.)

Source: The Development of Radio (PBS); History of Commercial Radio (FCC)