GDT > RTD Rider’s Guide > Routes > D Line
The original suburban extension…
Opened in October 1994 as part of the original “Metro Area Connector” (MAC) light rail project, the D Line originally ran between 30th / Downing and I-25 & Broadway via the Downtown Light Rail Loop. It was extended 8.7 miles to Littleton – Mineral in July 2000.
The C Line was introduced in April 2002 with the opening of the 1.8 mile Central Platte Valley spur to Denver Union Station and trains along the southwest corridor would alternate between having Denver Union Station and the 30th / Downing as their northern destination.
In 2018 RTD split the original D Line into two segments with the L Line taking over the northern portion from Downtown to 30th / Downing, while the D Line continued to serve the Downtown to Littleton – Mineral section.
The C Line was permanently suspended in January 2021 due to the COVID-19 pandemic, although unadvertised trains mimicking its route often operate for special events at Empower Field at Mile High.
D Line trains currently cover the 19 miles between Downtown and Littleton – Mineral in approx. 45 minutes.
Map & Schedule
The D Line operates from 5am to 12am, 7 days a week with extra late night round trips being operated on Friday and Saturday nights. 15 minute frequency service is provided from 6am to 8pm, frequency is 30 minutes outside of those times.
Vehicles Used
Usually requiring no more than a single car consist, both Siemens SD-100 and Siemens SD-160 light rail vehicles can be found operating on the L Line. It requires 7 trains to operate the 15 minute frequency service and 4 trains to operate the 30 minute frequency service.
The line is electrified at 750V DC throughout.
Ridership
| Year | Total |
| 2018 | 3,343,000 |
| 2019 | 3,005,000 |
| 2020 | 739,000 |
| 2021 | 1,901,000 |
| 2022 | 2,674,000 |
| 2023 | 2,666,000 |
Note: Figures from 2021 include former C Line riders.
Extension to Highlands Ranch
As part of RTD FasTracks program, there are plans to extend the D Line south towards C-470 in Highlands Ranch.