On Saturday during the football game with California, Colorado will celebrate the 50th anniversary of the Ralphie program.
While Ralphie I did actually run for the first time in 1966, there is no evidence of her leading the team onto the field until 1967 - the first year the program was endorsed by the university.
During the past five decades, the five Ralphies have thrilled the crowds at Folsom Field, as well as at other events throughout the year.
Here is a look at the legendary mascot's 50 years:
CU Boulder celebrates 50 years of running with Ralphie
A 'crazy idea' that became a tradition
Current, former players love chance to run with Ralphie
Ralphie has been known to strike fear in players, coaches
'Some people are totally obsessed with Ralphie'; CU Buffs fans have found memories of famous buffalo
Ralphie handlers part of long, 'amazing tradition' at CU Boulder
For CU Boulder's Ralphie mascot, a low-key life with occasional public cameos
When Ralphie V roamed free: The CU Boulder mascot's memorable 2008 debut