The H Line, part of the light rail system operated by the Regional Transportation District in the Denver-Aurora Metropolitan Area in Colorado, was added to the system on November 17, 2006, with the completion of the Southeast Corridor project (the "T-Rex Project").

It is one of four routes that were originally part of the RTD's service plan for the corridor.

[2] The 2004 voter-approved FasTracks initiative extended the H Line approximately 3.5 mi (5.63 km) to the north along Interstate 225 with stops at Iliff Avenue and Florida Avenue.

Work began in 2012, and the two station extension was combined with I-225 corridor light-rail line in 2013.

Construction was long expected to be completed in 2016,[3] however opening was delayed until February 24, 2017.