The Golden Subdivision began as Colorado Central’s Clear Creek line in the late 1800s. The line was originally built by the Colorado Central Railroad between Denver and Black Hawk. The construction to Silver Plume was completed in the following years.

The line fell into the ownership of the Colorado & Southern Railway in 1898 as a consolidation of bankrupt railroads around the area. In 1908, the line was in control by the Chicago, Burlington & Quincy Railroad until the merger into the Burlington Northern Railroad in 1981. The Burlington Northern Railroad later merged and became the BNSF Railway in 1996.

As business changes occurred with the larger class I railroads, BNSF Railway transferred operations of the Golden Subdivision between Denver and Georgetown to the Arvada Western Railroad in 2015.

The Denver, Leadville & Gunnison Railway (originally the Denver, South Park & Pacific Railroad) created the South Park Line in the 1870’s as a 3-foot narrow gauge line. The line began at Denver Union Station and followed the South Platte River south out of Denver and connected the cities Jefferson, Fairplay, and Como through Kenosha Pass. The line was eventually sold to the Colorado & Southern Railway.

The last train from Como over Kenosha pass was in 1937 and the line was shutdown by the Colorado & Southern. After the merger of the Colorado & Southern Railway into the Burlington Northern Railroad, the line was converted to standard gauge to Bailey after prospects of traffic returning. However, the line remained idle until the BNSF Railway transferred operations of the line to the Arvada Western Railroad in 2020.