Broadway’s bright lights gave it the nickname “Bulb Belt.” “No-bulb belt” (Off-Broadway) was cited in print in 1928. Broadway columnist Walter Winchell (1897-1972) used “Bulb Belt” in 1930.
 
Other nicknames for Broadway and its bright lights include “Great Bright Way,” “Great White Way,” “Incandescent District,” “Lane of Lights and Laughter,” “Mazda Lane,” “Street of the Midnight Sun” “Tungsten Territory” and “White Light Belt.”
   
 
Wikipedia: Broadway (Manhattan)
Broadway (/ˈbrɔːdweɪ/) is a road in the U.S. state of New York. Broadway runs from State Street at Bowling Green for 13 mi (21 km) through the borough of Manhattan and 2 mi (3.2 km) through the Bronx, exiting north from New York City to run an additional 18 mi (29 km) through the Westchester County municipalities of Yonkers, Hastings-On-Hudson, Dobbs Ferry, Irvington, and Tarrytown, and terminating north of Sleepy Hollow.
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Broadway in Manhattan is known widely as the heart of the American commercial theatrical industry, and is used as a metonym for it, as well as in the names of alternative theatrical ventures such as Off-Broadway and Off-off-Broadway.
 
Old Fulton NY Post Cards
2 October 1928, Standard Union (Brooklyn, NY), “‘Pleasure Man’ Is Given By Mae West” by D.T., pg. 15, col. 3:
Feminine hearts must be exceptionally susceptible in the no-bulb belt for the pleasure man would have bored any girl to death waiting for him to get into his killing-clothes.
(Vaudeville female impersonators in a small town.—ed.)
 
4 February 1930, San Luis Obispo (CA) Daily Telegram, pg. 5, col. 5:
As a representation of Broadway’s big bulb belt and Tin Pan Alley, the picture observes faith more so than many other recent productions with a similar background.
(The film “New York Nights.”—ed.)
 
8 May 1930, Richmond (VA) Times-Dispatch, “Walter Winchell On Broadway,” pg. 17, col. 1:
Among other unusual sights in the Bulb Belt: ...
 
26 May 1930, Evansville (IN) Courier, “Walter Winchell On Broadway,” pg. 4, col. 7:
Moore’s is one of the rendezvous in the Bulb Belt for the sportsmen and their “hearts.”
 
19 February 1932, Port Arthur (TX) News, “On Broadway” by Walter Winchell, pg. 4, col. 6:
For the first time in decades the 43rd St. and 7th Ave., SW corner, is naked—not a billboard or a bulb belt sign covering the edifice.
 
10 March 1935, San Diego (CA) Union, “‘Twas ‘Ladies Change’ in Broadway’s Maddest Marriage Dance,” magazine sec., pg. 6, col. 1:
His first wife was Emily Matthews, whose name stirs no memories in the Big Bulb Belt.
 
15 August 1962, San Diego (CA) Union, Frank Rhoades column (Walter Winchell, guest columnist), pg. B-1, col. 1:
Broadwayite strolling Broadway, San Diego: This immigrant from The Big Burg’s Bright-Bulb Belt gave up doing his col’m in the N.Y. Mirror skyscraper some years ago because some editor (or copy-boy) was sure to invade our cage (along side the AP and UPI tickers) and say: “How about some passes to ‘No Strings,’ ‘How to Succeed’ or ‘any other sellout show in town?’”
 
24 August 1971, The Plain Dealer (Cleveland, OH), “A Look at Walter Winchell” by Alvin Beam, pg. 13-A, col. 2:
For good enough reasons the phrases haven’t stayed with us but Winchell did invent, or was very early in borrowing, “Hardened Artery” and “Bulb Belt” for Broadway. With the Depression in mind he turned out “Hard Times Square” for Times Square.