The original rail corridor from Denver to Golden via Lakewood was constructed in 1892 as the Denver, Lakewood & Golden. In 1909, it was sold to the Denver & Inter-Mountain Railway, and was shortly electrified. By 1914 it was merged into the unified Denver Tramway system. Electric passenger service ended in 1950, and electrified freight ended three years later. The line passed to the Associated Railroad after the Denver Tramway ceased rail operations, and was operated to the Federal Center over the years by the AT&SF, C&S, and D&RGW. Eventually, freight traffic ceased and the line lay dormant for several decades.

From the Rocky Mountain Railroad Club Newsletter #22, May 1961:
Those of you who live in West Denver may have noticed a difference in train service on the Associated Railroad line which runs out to the Denver Federal Center. As of March 17, the D&RGW has been handling all of the freight traffic. The D&RGW will do this for 2 years, then the C&S for 3 years. Reason for this is the D&RGW handles it 1 year for the D&RGW and 1 year for the Rock Island, and the C&S handles it 1 year for the C&S, 1 year for the CB&Q, and 1 year for the Santa Fe.

RTD West Corridor

In 2009, the route was resurrected as RTD's West Corridor, the first light rail expansion of RTD's FasTracks program. After being completely rebuilt and extended, the corridor is expected to open to the public on 27 Apr 2013. Several rail-oriented groups, including the Rocky Mountain Railroad Club and the Colorado Railroad Museum, will be sponsoring a fan trip the weekend before it opens on 20 Apr 2013.