Warszawa Tram Map 2013: There is no Tramway Null Now in Warszawa

But was there a Tramwaj Null  (# 0) in Warszawa in 1920?  In 1920 to Muranów Ul.?  Which cities has a tramway or streetcar with the number = to Null= 0?

http://www.urbanrail.net/eu/pl/war/tram/warszawa-tram.htm

Clip above from:

Przedwojenna Warszawa 1936 / Prewar Warsaw

Source: UrbanRail.net from University of Texas at Austin Map Room