MN 23 was authorized November 2, 1920, from
Paynesville to
Mission Creek, south of
Hinckley. By 1933, the highway was paved between Roscoe and Cold Spring and from St. Cloud to Mission Creek. It was extended west to
Benson and east to Duluth in 1934. Various sections of the highway were paved from the 1930s through the 1950s; the entire length was paved by 1961. The section of present-day MN 23 from its southern terminus to Marshall was originally designated MN 39 until 1940. The section between Marshall and
Willmar was originally designated MN 17 until 1940. The MN 23 designation originally extended west from
New London to
Benson along the modern
MN 9; which was also MN 17 from around 1940 to the 1960s. MN 23 originally ran through
Sandstone proper to just west of
Askov along the route that later became
MN 123; this was redesignated 1946. From 1934 to 1963, the northern terminus for MN 23 was its junction with old
US 61 and
US 2 in
West Duluth. From 1963 to 1997, MN 23 continued farther into Duluth proper as a business route using several local arteries including Michigan Street, West 1st Street, East 2nd Street, East 3rd Street, and East Superior Street. The former northern terminus for MN 23 during this time period was at the intersection of US 61 (now MN 61) and 60th Avenue East in Duluth. In 1997, the official northern terminus changed to its junction with
I-35 at Grand Avenue in Duluth. After completion of the
I-35 freeway, the state maintained MN 23 through
Hinckley and Sandstone; now MN 23
runs concurrently with I-35 from Hinckley to Sandstone. The four-lane US 71 / MN 23
bypass of Willmar was proposed in the 1960s. However a financial crisis in the early 1980s led to the northbound lanes being unpaved, and the bypass had been scaled down to a two-lane facility by the time it opened in 1985. Construction in 2001 completed the bypass to its original four-lane design. The MN 23 expressway from
Spicer to
New London, and the expressway from
Richmond to
Waite Park (
St. Cloud), were both completed by 2005. In February 2008, a
bus crash occurred on MN 23 near
Cottonwood when a school bus carrying 28 students from Lakeview Public Schools was struck by a driver who ran through a stop sign which caused the bus to fall onto a pickup killing four students and injuring 17 others. The
DeSoto Bridge across the Mississippi River in St. Cloud was closed on March 20, 2008, after bent gusset plates were found in an inspection; similar to gusset plates that caused the
I-35W Bridge in
Minneapolis to collapse on August 1, 2007. The DeSoto Bridge was demolished in October 2008, and a new replacement bridge, the
Granite City Crossing, was completed on October 29, 2009. The Paynesville Bypass project began on April 26, 2010. The project consists of constructing a four-lane bypass around Paynesville, running from County Road 6 (CR 6) in Kandiyohi County to CR 123 in Stearns County. The project was completed in July 2012. The length of the new bypass is . The project includes grading, construction of eight bridges, surfacing and lighting, and it cost $32.2 million (equivalent to $ in ). Another project expanded MN 23 to four lanes from St. Cloud eastward to
Foley, which began July 1, 2011, and finished sometime in late 2012. This project expanded an segment of the highway. While this section is technically part of the St. Cloud-to-I-35 portion of the corridor (and thus has less overall priority), the increase in traffic along this particular stretch led to a decision to expand the highway, as there have been major safety and mobility issues the last couple decades due to growth in the St. Cloud area. ==Future==