The Regional Transportation District will debut a new December holiday service on its new light rail tracks in place of standard rail routes downtown.

And, no, this doesn’t mean downtown light rail trains D, H and L lines have returned after a months-long construction project.

Following the reconstruction of the light rail crossing at the intersection of Kalamath Street and Colfax Avenue, RTD will debut a temporary “Holiday Train” between Interstate 25/Broadway and the 30th/Downing Stations, according to a news release from the RTD. While the L Line won’t be operational at this time, the Holiday Train mirrors the exact route.

The new service will operate instead of the D, H and L lines, which will maintain their current schedule adjustments until Jan. 4. An RTD spokesperson confirmed that the delay is in accordance with the agency’s three-month schedule change period, which beings Jan. 3.

The train will run on a 15-minute frequency between 6 a.m. and 11:30 p.m. from Nov. 28 through Jan. 3, according to the release.

“After two months of steady work, these critical transit improvements have reached the final stretch,” said Angel Peña, RTD’s deputy chief executive officer, in the release. “The continued commitment of everyone will ensure we finish strong.”

Part of a $152 million project to reconstruct miles of light rail track through downtown, the project began last year and is expected to continue into 2026, according to the release. The next phases of the project will include Colfax Avenue alignment reconstruction, Downtown Loop midblock sections and Welton Street Corridor design work.

The current D, H and L line routes and Bus Routes 16 and ART will continue to be re-routed to Union Station until Jan. 3, according to the release. Those routes are as follows:

• The D Line will continue serving Union Station and trains will maintain their current, 15-minute frequency between Littleton/Mineral Station.

• The H line will continue operating between the Florida and Southmoor Stations on 15-minute frequencies.

• The L line will remain suspended, with Bus Route 43 available to support riders with connections along that corridor.

• The “Holiday Train” will provide connections every 15 minutes between the I-25/Broadway and 30th/Downing Stations, mirroring the L Line route.

Denver Gazette Reporter Noah Festenstein contributed to this report.