High School Colorado Mission and Retreat Since the 1980's, St. Luke's has had a rich tradition on doing a large summer retreat. This youth retreat takes place at the YMCA of the Rockies in Winter Park, Colorado. This years and final Colorado retreat will be June 13 - June 20. Each day begins with prayer and includes rafting, hiking, swimming, crafts, a ropes course, and games. Watch bulletin for dates of events.