State Highway 30 was established in 1933, originally running from Highway 15 to Rushford. It replaced former State Highway 41 from Blooming Prairie to Hayfield. The road was completely gravel at this time except where it overlapped other highways.[1][2]
By 1946, the road was still unpaved except for short sections in and near some towns.[4] The first extended paving was done from Cummingsville to Rushford in 1948 and 1949.[5][6] The remainder of the highway was paved throughout the 1950s; by 1960 it was fully paved.[7] In 1955, the highway was re-routed east of Chatfield to overlap with Highway 74.[6]
In 1961, Highway 30 was extended westward, along the route of what had previously been State Highway 47. (This highway number was simultaneously re-used on another highway in east-central Minnesota.) This extension was paved except for the section between U.S. 71 and the Cottonwood-Watonwan county line;[8][9] this section was paved in 1965.[10]
Highway 47 was originally established November 2, 1920 from Pipestone to Slayton.[11] It was extended west to the South Dakota state line and east to Highway 4 north of St. James in 1933. The entire highway was gravel at this time.[1][2] In 1939, it was realigned to take a direct route to Darfur from U.S. 71, bypassing Comfrey.[12][13][14] By 1940, the roadway was paved from the state line to Westbrook.[14] Paving from Westbrook to U.S. 71 was performed in 1950 and 1951, [15] and through Watonwan County in 1955.[12]
In the late 1970s, Highway 30's overlap with Highway 60 was upgraded to a four-lane expressway.[16]
^1960 Official Road Map, Minnesota (Map). Cartography by The H.M. Gousha Co. Minnesota Department of Highways. 1960. § G-19 through O-19. Retrieved December 2, 2018.
^1961 Official Road Map, Minnesota (Map). Cartography by The H.M. Gousha Co. Minnesota Department of Highways. 1961. § B-19 through G-19. Retrieved December 2, 2018.
^Minnesota State Legislature (2010). "§ 161.114, Constitutional Trunk Highways". Minnesota Statutes. Minnesota Office of the Revisor of Statutes. Retrieved December 2, 2018.
^1939 Map of Minnesota Trunk Highway System (Map). Cartography by McGill-Warner Co. Minnesota Highway Department. May 1, 1939. § F-21 through G-21. Retrieved December 2, 2018.