Mile Marathon

Celebrate the joy of running, the power of community, and nearly 50 years of tradition in Boulder’s oldest and longest-standing race. The Mile Marathon is the the year end celebration for the community at Columbine Elementary School, where students at Boulder’s bilingual public school run one mile around the school. This annual fundraising event kicks off the BOLDERBoulder 10K during the Memorial Day weekend, and shares a segment of the same course.

The Mile Marathon began in 1978 with a simple yet powerful idea. Two Columbine Elementary School teachers wanted to create a special event to celebrate the end of the school year. They enlisted local running legend Rich Castro—founder of the Boulder Road Runners, a key figure in starting the BOLDERBoulder, and instrumental in launching CU’s women’s running program. When Castro posed the question, “Why not host a running race around the school?” a beloved tradition was born. Today, that humble idea has grown into Boulder’s longest-standing race, inspiring generations of runners and bringing our community together year after year.