1885 - All horse car companies consolidated into Street Railway Co. of Grand Rapids.
1887 - Cable car service introduced by Valley City Cable Railway.
1890 - Street Railway Co. of Grand Rapids and Valley City Cable Railway merge into Consolidated Street Railway of Grand Rapids.
1891 - Conversion of cable car lines to electric streetcars begins.
1900 - Consolidated Street Railway of Grand Rapids sold to Grand Rapids Railway.
1902 - Grand Rapids, Grand Haven & Muskegon Railway completes interurban line between its namesake cities. Grand Rapids, Holland & Lake Michigan Rapid Railway Co. completes interurban line from Grand Rapids to Holland and Saugatuck.
1904 - Grand Rapids, Holland & Lake Michigan Rapid Railway Co. reorganized as Grand Rapids, Holland & Chicago Railway.
1910 - Commonwealth Power Railway & Light Co. incorporated, acquires Grand Rapids Railway Co. as a subsidiary.
1915 - Michigan Railway Co. completes interurban line from Grand Rapids to Kalamazoo, utilizing private right of way within Grand Rapids. Grand Rapids, Holland & Chicago Railway also begins using private right of way route within Grand Rapids.
1919 - Michigan Railway Co. reorganized to Michigan Railroad Co.
1922 - Commonwealth Power Co. incorporated as subsidiary of Commonwealth Power Railway & Light Co., controlling Grand Rapids Railway Co.
1923 - First bus route introduced in Grand Rapids.
1924 - Electric Railway Securities Co. incorporated as a separate new holding company, affiilated with Commonwealth Power Co. Grand Rapids Railway Co. becomes subsidiary of Union Railway Gas & Electric Co., formerly a subsidiary of Commonwealth Power Co.
1926 - Grand Rapids, Holland & Chicago Railway abandons line. Michigan Railroad Co. abandons private right of way route within Grand Rapids, using instead using local streetcar route.
1927 - Grand Rapids Railway Co. reorganized as Grand Rapids Railroad Co.
1928 - Grand Rapids, Grand Haven & Muskegon Railway and Michigan Railroad Co abandon lines, ending interurban railway service in Grand Rapids.
1930 - Grand Rapids Railroad Co. becomes separate company from Union Railway Gas & Electric Co.
1935 - Last local streetcar service replaced with buses.
1938 - Grand Rapids Railroad Co. renamed Grand Rapids Motor Coach Co.
1954 - Grand Rapids Motor Coach Co. sold to City Coach Lines Inc., renamed Grand Rapids City Coach Lines.
1963 - Grand Rapids City Coach Lines becomes publicly owned Grand Rapids Transit Authority.
1978 - Grand Rapids Transit Authority becomes Grand Rapids Area Transit Authority.
2000 - Grand Rapids Area Transit Authority becomes known as Interurban Transit Partnership.