The route ran from the downtown Denver interurban loop, along Lakewood Gulch and 13th Avenue, continuing out to Golden.

[2] Plans to resurrect a railway line from Denver to Golden were advanced in the mid-1970s and in the 1980s RTD purchased the right-of-way to an unused rail corridor between the two cities.

[3] A study conducted in 1997 stated the need for a rapid transit corridor through the region, and settled on 13th Avenue as the locally preferred alternative.

[6] The first full test run of the line happened on January 3, 2013, in anticipation of the official opening, April 26, 2013, eight months ahead of schedule.

Some of the route goes through residential areas and concerns about noise led to an innovative solution for the warning system at crossing gates.