RTD E Line Train 305 southbound at Broadway Station.

(FoamingInDenver, CC0, via Wikimedia Commons)



The Regional Transportation District, more commonly referred to as RTD, is the regional agency operating public transit services in eight out of the twelve counties in the Denver-Aurora-Boulder Combined Statistical Area in the U.S. state of Colorado. It operates over a 2,342-square-mile (6,070 km2) area, serving 3.08 million people. RTD was organized in 1969 and is governed by a 15-member, publicly elected Board of Directors. Directors are elected to a four-year term and represent a specific district of about 180,000 constituents.

RTD currently operates a bus and rail system that has a service area of 2,342 square miles (6,070 km2). It currently runs 86 local, 23 regional, 14 limited, and 3 skyRide bus routes plus some special services. It also includes 6 light rail lines and an additional 4 commuter rail lines with 77 stations and 113.1 miles (182.0 km) of track.

In 2023, the system had a ridership of 65,021,500, or about 238,500 per weekday as of the first quarter of 2024. It employed 2,888 people. It had a $675.5 million operating budget for the year of 2018. Google has RTD schedules attached to its trip planner, and 3rd party mobile applications are now available for the iPhone and other platforms.

RTD is constructing the voter-approved FasTracks transit expansion that will add 122 miles (196 km) of new commuter rail and light rail, 18 miles (29 km) of rapid transit bus service, 21,000 new parking spaces at rail and bus stations, and enhance bus service across the eight-county district.


Denver RTD Rail Map.

(Haha169, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)



Light rail

RTD began planning for a light rail in the mid-1980s, after the successful opening of the San Diego Trolley in 1981 and amid a surge in light rail construction in mid-sized cities nationwide (Buffalo, Portland, Sacramento, and San Jose also built systems at the same time).

RTD's first line, the 5.3-mile (8.5 km) Central Corridor between the 30th & Downing and the I-25 & Broadway stations (now part of the D Line and L Line) opened on Friday, October 7, 1994. It operated with free service for that first weekend, with revenue service starting on October 10. More than 200,000 passengers rode the new system during its opening weekend, when the fleet comprised only 11 Siemens SD-100 rail cars.

The 8.7-mile (14.0 km) Southwest Corridor light rail extension to Mineral Avenue in Littleton opened in July 2000, followed by the 1.8-mile (2.9 km) Central Platte Valley spur to Denver Union Station in April 2002. In 2003, the downtown portion of the original line between Speer Boulevard and 14th Street was realigned as a result of construction of the Colorado Convention Center.

In April 2006 transit workers of the Amalgamated Transit Union went on strike for the first time in 24 years, citing increased health care costs, mandatory overtime, and disproportionate wage increases relative to upper management. Workers walked off on April 3, shutting down the light rail system and decreasing bus service to about 45% of its normal capacity. A revised contract was approved by the union on April 7, and service resumed on April 10. The strike lasted seven days, and although thousands of commuters were stranded by the strike, only a few backups were reported as customers made makeshift arrangements for commuting or waited out the strike.

The 19-mile (31 km) Southeast Corridor, a component of the Transportation Expansion Project, opened on November 17, 2006, along I-25 to Lone Tree and a branch along I-225 to Parker Road. The West Rail Line opened on April 26, 2013. As of April 2013, the system had 170 light rail vehicles, serving 47 miles (76 km) of track.

The light rail R Line to Aurora and Lone Tree opened on February 24, 2017.

RTD made significant service changes and suspended service on multiple bus and light rail lines due to the COVID-19 pandemic. The F line was suspended on September 20, 2020 and the C Line was suspended on January 10, 2021, with both routes being permanently discontinued in early 2023.


Union Station is the main interchange between the commuter rail and light rail systems; local, regional, and intercity bus lines; and Amtrak.

(Shreeg88 at en.wikipedia, CC BY 2.5 <https://creativecommons.org/licenses/by/2.5>, via Wikimedia Commons)


Commuter rail

With the voter approval of FasTracks in 2004, RTD began planning for a series of commuter rail lines. The first 23.5 miles (37.82 km) of which, the A Line servicing Denver International Airport, opened on April 22, 2016. The second, the first 6.2 mile segment of the B Line, officially opened on July 25, 2016.

As one of the first new commuter rail systems in the country planned after enactment of the Rail Safety Improvement Act of 2008, positive train control (PTC) and vehicle monitoring system technologies are implemented along the system's commuter train lines. After the A Line opened between Denver Union Station and Denver International Airport, it experienced a series of issues related to having to adjust the length of unpowered gaps between different overhead power sections, direct lightning strikes, snagging wires, and crossing signals behaving unexpectedly. In response, Denver Transit Partners, the contractor building and operating the A Line, stationed crossing guards at each place where the A line crosses local streets at grade while it continued to explore software revisions and other fixes to address the underlying issues. The Federal Railroad Administration allowed RTD to open its B Line as originally scheduled on July 25, 2016, because the B Line only has one at-grade crossing along its current route that is not designated to be a quiet zone. However, FRA previously halted testing on the longer G Line to Wheat Ridge – originally scheduled to open in late 2016 – until more progress could be shown resolving the A Line crossing issues. On April 26, 2019, the G Line opened to the public.


Accidents and incidents

On January 28, 2019, an R Line light rail train derailed the junction of East Exposition Avenue and South Sable Boulevard (between Aurora Metro Center and Florida stations) due to excessive speed. The curve has a speed limit of 10 mph (16 km/h) but the train approached at 38 mph (61 km/h). One woman's foot was amputated by the train wheels after she was ejected from the car during the accident, eight other passengers were also injured. Although determined responsible for the accident, no charges were filed against the driver.

On September 21, 2022, another derailment occurred at the same location. Three people were taken to hospital with injuries that were not believed to be life threatening. Video showed the train approaching the turn at high speed, although as of September 29, 2022, no cause has been officially released.


Current services

The primary RTD services are scheduled bus and rail routes.

Most bus routes are divided into Local and Regional service levels.

Rail services are divided into two fare zones: local and airport. Local and regional service is within the local zone. The airport zone applies for bus or rail travel into and out of Denver International Airport.


MallRide bus.

(Jeffrey Beall, CC BY 4.0 <https://creativecommons.org/licenses/by/4.0>, via Wikimedia Commons)


Bus Services

Bus service in Denver dates back to 1924, when Denver Tramway began the first bus between Englewood and Fort Logan. Buses had completely replaced the previously expansive streetcar system in metro Denver by 1950, and the privately owned Denver Tramway served the City and County of Denver, as well as older portions of Arvada, Aurora, Englewood, Golden, Lakewood, Westminster, and Wheat Ridge and smaller suburbs.

For more information on bus services, click HERE.


Special services

Special bus services are offered for various purposes.

  • Access-a-Ride: Paratransit service providing local bus transportation in the Denver metro area for people with disabilities and cannot access the fixed-route bus and train system.
  • FlexRide: On-demand shuttle service connecting less densely populated areas without fixed-route bus and rail service to nearby transportation hubs.
  • Flatiron Flyer: Express bus service between Boulder and various locations in Denver.
  • Free MallRide: A free shuttle bus service that runs the length of the 16th Street Mall, connecting three major RTD transportation hubs (Union Station, California/Stout station, and Civic Center Station).
  • Free MetroRide: A free shuttle bus service that runs parallel to the MallRide on 18th and 19th Streets, but operates faster by making fewer stops between Union Station and Civic Center Station.
  • SeniorRide: Point-to-point shuttles for groups of 10 or more seniors, and scheduled service between shopping centers and senior housing complexes/community centers.
  • SkyRide: Airport shuttle/express bus service for travelers heading to Denver International Airport
    Sporting events service:
    • "BroncosRide", which provides direct service to Broncos Stadium at Mile High from various locations around the metro area.
    • "RunRide", a similar service which provides direct service to Boulder during the Bolder Boulder 10K road race.


Civic Center Station after renovation in 2017.

(Jeffrey Beall, CC BY 4.0 <https://creativecommons.org/licenses/by/4.0>, via Wikimedia Commons)


Bus stations

Major bus stations provide termini for express and regional routes. Many local and limited routes stop near these stations, making transfers between routes relatively easy. Of the three major bus stations in the RTD system, only one—Union Station—is also served directly by light rail trains. None of the three major bus stations is a Park 'n' Ride facility. Civic Center Station is connected to Union Station via the Free MallRide and Free MetroRide shuttle.

Station Name Address
Civic Center Station 1550 Broadway, Denver
Union Station (rail and bus) 1701 Wynkoop Street, Denver
Downtown Boulder Station 1400 Walnut Street, Boulder


A number of rail stations in the RTD system, as well as a number of bus stops located away from the three major bus stations, are attached to dedicated RTD parking facilities. These are the Park-n-Ride locations. There are 92 RTD Park-n-Ride facilities with an aggregate total of more than 30,000 parking spaces.


Rail services

The current commuter rail lines are:

Line Opening Length Stations Termini
A Line April 22, 2016 23.5 mi (37.8 km) 8 Union Station Denver Airport
B Line July 25, 2016 6.2 mi (10.0 km) 4 Union Station Westminster
G Line April 26, 2019 11.2 mi (18.0 km) 8 Union Station Wheat Ridge/Ward
N Line September 21, 2020 13 mi (21 km) 7 Union Station Eastlake/124th

The current light rail lines are:

Line Opening Stations Termini
D Line October 7, 1994 12 18th & California Littleton–Mineral
E Line November 17, 2006 21 Union Station RidgeGate Parkway
H Line November 17, 2006 16 18th & California Florida
L Line January 14, 2018 6 16th & California/Stout 30th & Downing
R Line February 24, 2017 19 Peoria RidgeGate Parkway
W Line April 26, 2013 15 Jefferson County Government Center–Golden Union Station

Littleton-Mineral light rail station.

(vxla from Chicago, US, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons)


Rail Stations

Many of the Light Rail and Commuter Rail stations have gates for various bus services. There are 77 stations on the ten lines in the RTD Rail system. RTD has adopted specific design standards that are incorporated into its station design, with a specific emphasis on the platform, its transition plaza and the multi-modal access provided at the facility. Platforms are designed to accommodate three or four car Light Rail trains in addition to two car or four car Commuter Rail trains and may be in either a side, island or side center style. The transition plaza is the area where tickets are purchased and passenger services can be found. Additionally, all stations include works of public art as part of RTD's art-n-Transit program. These works include independent works or as pieces incorporated into the canopies, columns, pavers, windscreens, fencing and landscaping present at all stations.


RTD Line D – Mineral Station/18th and California St train in downtown Denver. (vxla from Chicago, US, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons)

RTD A Line train at Denver Union Station. (Xnatedawgx, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)

Interior of a RTD light rail train. (The original uploader was Gtony40404 at English Wikipedia., CC BY-SA 2.5 <https://creativecommons.org/licenses/by-sa/2.5>, via Wikimedia Commons)


Gillig Low Floor buses make up most of the fleet, replacing the Orion V and Gillig Phantom buses that made up most of the fleet until the late 2000s. In 2014, RTD began to receive New Flyer Xcelsior low floor buses for the free MetroRide and other routes. MCI and Neoplan vehicles are used as express buses and regional buses, including service to Denver International Airport branded as SkyRide. In 2016, RTD began receiving delivery of 36 BYD K10MR all-electric buses to be used on the 16th Street Mall, replacing the older locally built TransTeq EcoMark buses in use since 2001.

Siemens SD-100 and SD-160 are used as light rail vehicles. As of May 2015, the RTD light rail fleet had 172 light rail vehicles, serving 58.5 miles (94.1 km) of track and 54 stations. For RTD's new commuter rail system, it uses Silverliner Vs.


Map of RTD rail service and fare zones as of July 2023.

(RTD, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)



The RTD fare structure is based on a zone system for rail and a service level system for bus. Since the start of 2024, local/limited bus routes or a trip on rail costs $2.75, and travel on bus or rail to Denver International Airport costs $10. Seniors, students, people with disabilities, and Medicare recipients are eligible for reduced fares. Children below age 6 ride free when accompanied by an adult with proper fare; this offer is limited to three such children per adult passenger. RTD also offers daily passes: Local ($5.50) and Regional/Airport ($10) which allow unlimited travel at the chosen fare level until 2:59 a.m. the day following the purchase.

The fare system was last updated in January 2024, after conducting a fare study from April 2022 to July 2023. Users mentioned that fares were expensive to begin with, and the zone system made understanding fares complicated. The changes resulted in a simplification of the fare structure of the system, as well as lower costs. Prior to this update, the rail system was divided into local, regional, and airport zones, costing $3.00, $5.25, and $10.50 respectively.

A fare card program, in development for over four years by Xerox, is available through employers as the EcoPass, through colleges as the CollegePass, and to the general public as the MyRide Stored Value card. MyRide users receive a discount on fares.

RTD enforces transit code and fares with its own transit police, as well as via contracts with local police departments and Allied Universal Security Service.

The A, B, G, and N commuter lines require a crew member on each run. This member is responsible for enforcing fares and security. The light rail lines (D, E, L, R, and W) do not require such a member, and fares are enforced through random inspection.



In 2006/2007, RTD worked with the city of Boulder, the University of Colorado, and real-time bus-tracking outfit NextBus on a GPS-based system to help riders with bus arrival information at selected high-traffic stops, but the experiment proved to be unreliable and was discontinued. Several years later, RTD started making its bus location and route data available to third-party developers. Google Maps (website and mobile apps) started offering real-time bus information, as did various other mobile app developers with free or paid apps, such as the Transit app. In March 2017, RTD rolled out a new web-based tracking system, optimized for mobile devices, called Next Ride to track buses and light rail, predict arrivals, show nearby stops and routes.


Mobility as a service (MaaS)

In February 2019, RTD became the first transit authority to integrate its public transport services into the Uber app, enabling Uber riders in Denver to select a new ‘Transit’ option within the app, powered by Moovit Transit APIs. Uber Transit users can plan their journey with real-time information and step-by-step directions. Included in this is the ability to purchase transit mobile tickets directly in the app, powered by Masabi's Justride mobile ticketing SDK.



Downtown Express

This project added HOV lanes to I-25 north of downtown Denver. It also added several dedicated slip ramps for RTD buses to access several Park-n-Ride stations directly from the highway. At the south end of the HOV lanes, buses had direct routes into Union Station or Market Street Station. The HOV lanes extended from I-25 to US 36, allowing regional and express routes running along US 36 to downtown Denver to bypass congestion around the Turnpike Tangle. This project was completed in September 1994.

In 2006, the Downtown Express was renovated to include a toll lane, thereby converting the HOV lanes into high-occupancy toll lanes. This allows single-occupancy vehicles to pay a toll to use them. It was built to increase the overall usage and efficiency of the highway's HOV lanes. The project was completed on June 2, 2006.


I-25 & Broadway light rail station.

(Mobyll at English Wikipedia, Public domain, via Wikimedia Commons)


Central Corridor

The Central Corridor, a 5.3-mile (8.5 km) light rail line, opened in October 1994. It was built along Welton Street, through the Five Points district along Stout Street and California Street, and following a railroad right-of-way from Colfax Avenue down to the intersection of I-25 and Broadway. This line was built without the aid of tax increases or federal funds; however, extensions have been funded by the Federal Transit Administration and new tax measures. This line was built from 30th/Downing as the northern terminus to I-25/Broadway as the southern terminus.


Southwest Corridor

After the success of the Central Corridor, the Southwest Corridor light rail route opened in July 2000. An 8.7-mile (14.0 km) light rail line, the route runs from the terminus of the Central Corridor at I-25 & Broadway to Mineral Avenue in Littleton with five existing stations. The line has been popular, and the Park-n-Ride lots at its stations often experience parking shortages. This project built a light rail line from I-25/Broadway south to Littleton/Mineral alongside existing freight tracks used by BNSF and Union Pacific next to Santa Fe Drive.


Central Platte Valley Corridor

In April 2002, the Central Platte Valley (CPV) spur opened. It is a 1.8-mile (2.9 km) branch with four stations that provides light rail access to numerous venues, including the Auraria Campus, Broncos Stadium at Mile High, Ball Arena, Elitch Gardens, Union Station and Coors Field. This project built light rail lines from 10th/Osage to Union Station.


Louisiana-Pearl light rail station.

(Mobyll at en.wikipedia, Public domain, via Wikimedia Commons)


T-REX Project

In November 1999, Denver area voters approved a project, known as the T-REX, which involved reconstruction of I-25 between Broadway and Lincoln Avenue in Lone Tree, and I-225 between I-25 and Parker Road in Aurora, with widening of the road to five lanes and light rail being built. The highway project was completed on August 22, 2006. The light rail line, known as the Southeast Corridor, opened shortly after 11 a.m. on November 17, 2006. The line covers 19.1 miles (30.7 km) and includes thirteen new stations, with parking available at all but the Louisiana/Pearl station.


W Line train at Jefferson County station heading back to Union Station in Denver.

(Skyviper73, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)


West Rail Line
The West Rail Line opened on April 26, 2013. It was the first completed rail line of the RTD FasTracks Project. The 12.1 miles (19.5 km) of light rail run between Denver Union Station and Jefferson County Government/Golden Station, adding 11 new stations, 6 park-n-rides, and 3 new call-n-rides.



FasTracks is a major project underway to expand the Denver metro area's light rail and bus service and to add commuter rail service. A 2004 referendum approved tax increases to support FasTracks. As of December 2020, completed sections include the W Line to Golden (formerly West Line, light rail, opened 2013), the US 36 Bus Rapid Transit lanes and service to Boulder (Flatiron Flyer, 2016), the redevelopment of Union Station and surrounding area as a transportation hub and transit-oriented development (2014), the free MetroRide downtown circulator (bus, 2014), a segment of the B Line to Westminster (formerly Northwest Line, commuter rail, 2016), the University of Colorado A Line to Denver International Airport (formerly East Line, commuter rail, 2016), the R Line from Peoria Station in Aurora to Lone Tree Station (formerly I-225 Line, light rail, 2017), the G Line to Arvada (formerly Gold Line, commuter rail, 2019), the N Line to Thornton (formerly North Metro Line, commuter rail, 2020) and the E Line, F Line, and R Line extensions (Southeast Extension, light rail, 2019).

Extensions to the Southwest Light Rail Corridor, the L Light Rail Line, and the B and N Commuter Rail lines are planned via the FasTracks project. A BRT on East Colfax Avenue is also planned. Scheduled completion dates for remaining segments extend as far ahead as 2044.


Art on the light rail system

In 1977, Colorado passed the Art in Public Places bill which required that 1 percent of all state-funded construction budgets be used to purchase art. About $1 million from the T-REX contingency budget was dedicated to art projects at each of the 13 new southeast corridor light rail stations as part of RTD's art-n-Transit program.

  • Ira Sherman, "Stange Machine," Louisiana/Pearl Station
  • Ries Niemi, "Big Boots," Colorado Station
  • John Goe, "Reflective Discourse," University Station
  • Gregory Gove, "Connected," Yale Station
  • Chris Janney, "Harmonic Pass: Denver," Southmoor Station
  • Richard Elliott, "Thunder Over the Rockies," Belleview Station
  • Christopher Weed, "Windswept," Dayton Station
  • Dwight Atkinson, "Yet Another Way To Know That Nature Will Eventually Win," Nine Mile Station
  • Wopo Holup, "Orchard Memory," Orchard Station
  • Michael Clapper, "Nucleus," Arapahoe at Village Center Station
  • John McEnroe, "Fools Gold," Dry Creek Station
  • Emmett Culligan, "Plow," County Line Station
  • Ray King, "Sun Stream," Lincoln Station

Design team artists who worked on windscreen benches, railings, bike racks and canopy columns at all stations were Susan Cooper and Rafe Ropek.



Owner: Regional Transportation District
Locale: Denver Metro Area, Colorado
Transit types: Bus, Commuter rail, Light rail
Number of lines: 127 (Bus); 4 (Commuter rail); 6 (Light rail)
Number of stations: 57 (Light rail); 22 (Commuter rail)
Daily ridership: 29,100 (commuter rail, weekdays, Q1 2024); 51,200 (light rail, weekdays, Q1 2024); 154,600 (bus, weekdays, Q1 2024)
Annual ridership: 8,559,700 (commuter rail, 2023); 12,740,600 (light rail, 2023); 42,735,300 (bus, 2023)
Chief executive: Debra Johnson
Headquarters: 1660 Blake Street, Denver, Colorado
Website: rtd-denver.com
Began operation: 1969 (Bus); 1994 (Light rail); 2016 (Commuter rail)
Reporting marks: RTDC, RTDZ
Number of vehicles: 1,026 (Bus); 267 (Rail)
System length: 113.1 mi (182.0 km) (60.1 mi (96.7 km) light rail, 53 mi (85 km) commuter rail)
Track gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Electrification: Overhead line, 750 V DC (light rail) or 25 kV 60 Hz AC (commuter rail)


See Also:

Railroads A-Z