The BNSF Brush Subdivision is a busy mainline in northeastern Colorado, originally built by the Chicago, Burlington & Quincy Railroad between Denver and Brush, passing through Commerce City, Brighton, Hudson, Keenesburg, Roggen, Wiggins and Fort Morgan. Additionally, the CB&Q built an extension for the mainline northeast after Brush that connects to the UP Julesburg Subdivision via Hillrose and Messex, connecting to Sterling.
The Brush Sub was first built in 1882 by the CB&Q as part of the mainline from Denver to Chicago. In 1900, the CB&Q built their extension from Brush to Sterling, which involved trackage rights on the UP Julesburg Sub from Messex to Sterling. The Brush Sub was also home to the CB&Q's passenger route, the Zephyr. CB&Q was absorbed into Burlington Northern in the 70's, and later the BNSF in 1995. Today, the line is mostly used by Powder River Basin coal trains and Amtrak California Zephyr.
