The Toronto and Mimico Electric Railway and Light Company was incorporated in 1890, and operated the Mimico radial line in the Toronto area. The line started operation in 1892 as a short suburban line that later was extended to Port Credit. In 1904, the railway was acquired by the Toronto and York Radial Railway (T&YRR) and became the T&YRR Mimico Division. In 1922, the City of Toronto acquired the T&YRR and contracted Ontario Hydro to manage the four T&YRR lines including the Mimico line. In 1927, the TTC took over the operation of the Mimico line and extended its service eastward to Roncesvalles Avenue. In 1928, the TTC double-tracked the line from Humber to Long Branch and made that portion part of the Lake Shore streetcar line. The portion beyond Long Branch to Port Credit became the P