From 1966 until 2000, KRBI-FM simulcast with its AM sister at 1310 AM. In later years, the FM station aired an adult contemporary format, with a heavy focus on its hometown of St. Peter. After increasing power from 3,000 to 25,000 watts, improving its signal into Mankato and other nearby cities, KRBI-FM flipped to a more regionally-focused classic rock format as "River 105" on September 12, 2000. The St. Peter-oriented programming shifted to its AM sister, KRBI 1310 AM.
KRBI-FM switched its moniker to "The Buzzard" in April 2006.
On January 4, 2010 KRBI-FM changed their format to classic hits, branded as "105.5 The River".