1906 - Illinois Traction Co. acquires all street railways in Peoria.
1923 - Illinois Traction Co. introduces its first bus route, a feeder route connecting with East Peoria streetcar line. At the time, at least two independent bus routes were operating in Peoria.
1923 - Illinois Power & Light Co. formed as subsidiary of Illinois Traction Co., controlling the electric railways. North American Light & Power Co. acquires Illinois Traction Co. as a subsidiary.
1924 - Illinois Power & Light Co. takes over two independent bus lines in Peoria.
1927 - First streetcar routes to be converted to buses are on 2nd St, and on 6th St.
1931 - Monroe St. route converted to trolleybuses. This would be the only trolleybus route in Peoria.
1934 - North American Co. acquires North American Light & Power Co. as a subsidiary.
1937 - Illinois Power & Light Co. renamed Illinois-Iowa Power Co.
1943 - Illinois-Iowa Power Co. renamed Illinois Power Co., after being ordered to sell electric utility operations in Iowa.
1946 - Illinois Power Co. sells Peoria transit operation to Peoria Transportation Co., with ties to National City Lines. All remaining streetcars and trolleybuses replaced with buses.
1950 - Peoria Transportation Co. sold to Peoria Transit Lines Inc., also with ties to National City Lines.
1955 - Peoria Transit Lines sold to Transit Casualty Co., which was largely owned by National City Lines, and is renamed Peoria City Lines.
1964 - Peoria City Lines sold to new owners.
1970 - Peoria City Lines becomes publicly owned Greater Peoria Mass Transit District, managed by ATE Management.