The Garmin Olathe Marathon in the Land of Oz boasts a rich history that traces back to its inception in 2002. Initially, it served as the marathon course for the NAIA Outdoor Track and Field National Championships. The following year, in 2003, the NAIA opened the course to the public, allowing runners to participate 30 minutes behind the student-athletes. This marked the official beginning of the Olathe Marathon, attracting 183 enthusiastic participants.

In 2004, the marathon started at the Olathe District Activity Center and concluded at the Great Mall of the Great Plains, setting the stage for future events. From 2005 to 2008, the race began at Gardner-Edgerton High School and finished in downtown Olathe, providing runners with a scenic and challenging route. A significant change occurred in 2009 when the marathon started and finished at Garmin Headquarters in Olathe, establishing a strong connection with the local community and the company.

A transformative moment in the marathon’s history came in 2011 when the Wizard of Oz theme was introduced, rebranding the race as the Oz Marathon. This change significantly increased its popularity, drawing over 1,800 participants. In 2012, Garmin elevated its sponsorship to become the title sponsor, and the event was renamed the Garmin Marathon, while still embracing the beloved Wizard of Oz theme.

By 2014, the Garmin Marathon became part of the Heartland Series Half Marathons, boosting registration to nearly 4,000 runners. In 2016, the race found a new home for its start and finish line at the newly built Embassy Suites Hotel & Olathe Conference Center, hosting more than 3,700 runners from five countries and 44 states. The following year saw participation soar to over 4,100 runners from 43 states and 10 countries.

In 2018, the Garmin Marathon returned to Garmin World Headquarters for its 16th annual event, welcoming over 4,300 participants from all 50 states and 10 countries. The marathon continued to grow, featuring a Marathon, Half Marathon, 10K, Family Run, and Virtual Race, solidifying its reputation as a premier running event in Kansas.