[2] On June 1, 1907, the T&YRR opened a 40 km (25 mi) extension of the Metropolitan line from Newmarket to Jackson's Point.

[3] On January 1, 1909, the T&YRR opened a 2.4 km (1.5 mi) extension of the Metropolitan line from Jackson's Point to Sutton.

[5] By fall, 1921, the TTC took over the portion of the Metropolitan line on Yonge Street south of Glen Echo Road (at the city limit).

[6] On November 1, 1922, operation of the T&YRR was taken over by Hydro Electric Power Commission of Ontario and run as the Hydro-Electric Railways: Toronto and York Division.

Hydro blamed the TTC's acquisition of the profitable portions of the radial lines within the city limits.

[6] By 1925, Toronto City Council felt that integrating the radials within TTC operations would produce efficiency by avoiding duplication of carhouses and shops, by allowing the transfer of vehicles between radial and city lines to meet passenger demand, and by having firmer control over expenditures.

[8] The TTC now operated the second largest electric railway in North America with 585 kilometres (364 mi) of lines.

[6] On July 17, 1930, the TTC reopened a portion of the defunct Lake Shore line between Richmond Hill and Toronto as the North Yonge Railways.

[2] On October 9, 1948, service was terminated on the North Yonge Railways, the last surviving Toronto radial.

Standard gauge allowed the Metropolitan to exchange freight cars with steam railways.

[11] Unlike the city systems, the radial (interurban) operators used larger rail cars.

Radial routes ceased due to introduction of inter-urban buses and new highways that allowed for better access to many areas served by rail service.