This mural depicts Streetcar 504, which runs on Roncesvalles Avenue. This street is a center of Polish neighbourhood and was recently rejuvenated!
Some people call this streetcar Desire, because it never comes, when you need it! (Tennessee Williams wrote even a play about it) ;- )
It is in my old neighbourhood, I used to live there for about 5 years. There are several large murals on this short main street, this one was there at least since 2006!