Complex sentence: Longo's was founded by Tommy, Joe, and Gus Longo in 1956, who established their first store at the intersection of Yonge Street and Castlefield Avenue in Toronto.
Split into simpler sentences: Longo's was started by Tommy, Joe, and Gus Longo in 1956. The first store was located at the intersection of Yonge Street and Castlefield, in Toronto.