The line was added to the system on April 5, 2002, to coincide with the opening of the Central Platte Valley Spur.

Initially, C trains operated seven days a week, but ran to Littleton–Mineral station only during peak hours and sporting events.

With the opening of the Southeast Corridor on November 17, 2006, weekend C service was discontinued except for certain sporting events, with the new E line operating seven days per week.

The C Line was suspended on January 10, 2021 as part of broader service cuts in response to ridership decreases related to the COVID-19 pandemic.

[3] In addition, the C Line provided access to the sports venues of Denver – Coors Field, Pepsi Center, and Broncos Stadium at Mile High – Six Flags Elitch Gardens, and LoDo, as well as access to the western portion of the Auraria Campus.