Mecca of Telephone Men

Around 1900, when the telephone was new, New York City was the "mecca of telephone men." The nickname was rarely used then and quickly died, but it's sometimes given in lists of New York City nicknames.


Google Books
The History of the Telephone
By Herbert Newton Casson
Chicago, IL: A. C. McClurg & Co.
1910
Pg. 271:
China, Japan, and France have sent delegations to New York City -- "the Mecca of telephone men," to learn the art of telephony in its highest development.

11 July 1913, New York (NY) Times, pg. 11 ad:
"New York is the
Mecca of Telephone Men."
(...)
New York Telephone Company