Longest microwave relay system opened for transcontinental telephone service

The first telephone call Coast-to-coast along the new microwave radio-relay skyway of the Long lines Department of the American Telephone and Telegraph Company was made on August 17, 1951. Supplying a new backbone telephone route, vital to civilian and military needs of the nation, the project is the longest microwave system in the world. The new facilities for the first time will send telephone conversations across the continent by radio rather than wire or cable.