Bell System ad circa 1977~1978 in Spain.

Almost anywhere in the world you find yourself, you can find a phone. Then just tell the operator you want to place an international call, and you'll be back in touch with your family, friends, or business in no time—for less than you think. And phoning ahead when you plan your trip helps make it a smotth one, too. Long Distance is the next best thing to being there.

Bell System Long Distance | Bell System Long Lines

Backup: https://imgur.com/a/uVe6x

This film explains the Bell System from a blue-collar POV, from a "telephone man" He divides the Bell businesses into 5 segments, and explains what each of them do. It's faux-folksy, but it does the job.

Here are the company segments:

1. AT&T
2. Large local telephone companies (23 of them, like Mountain Bell, Pacific Bell, Ohio Bell, etc)
3. Long Lines
4. Bell Laboratories
5. Western Electric

Most people at the time knew of the Bell System as the company that rented you your phone, serviced the lines and provided basic and long distance telephone service. But the company extended far beyond that into military communications support operations, a number of much smaller subcompanies, and international telephony infrastructure projects.

Footage courtesy of AT&T Archives and History Center, Warren, NJ

Vintage telephone network sounds part 2 by Evan Doorbell.

Vintage telephone network sounds part 1 by Evan Doorbell.