Opened in 1984, it is Florida's only rapid transit metro system, and is currently composed of two lines of 23 stations on 24.4 miles (39.3 km) of standard gauge track.

The new line has helped increase ridership significantly, adding millions of riders per year[5] and allowing residents and visitors alike direct access from MIA to Downtown Miami, as well as greater connectivity between various modes of transit throughout Miami-Dade County.

The station provides direct service to Tri-Rail commuter rail, Greyhound Lines intercity bus, and the Rental Car Center.

[10] In June 1983, the first segment of Metrorail, 10 stations from Dadeland South to Overtown (now "Historic Overtown/Lyric Theatre") was completed with the construction of the Miami River Bridge.

[8] With the area having a generally low density and lacking transit-oriented development,[12] the Metrorail was designed as a park and ride system, with the idea being that suburban residents would drive to the stations, then commute the rest of the way into the city.

Several have large parking garages, such as Dadeland North and South stations, located at the southern end of the system, which combined have space for over 3,000 cars.

[13][14] Earlington Heights, located just northwest of Downtown and adjacent to Interstate 95 and the Airport Expressway, has a large garage that was formerly dedicated to Metrorail riders.

[16] The successful Dadeland garages are at or over capacity, with two of Metrorail's proposed extensions, the West Kendall Corridor and South Link, intended to help alleviate them.

President Ronald Reagan commented that, given the low number of riders, it would have been cheaper to buy them all a limousine than the billion dollar cost of building and subsidizing the system.

[15] This part of the system also has a higher average speed, having fewer curves and long distances between stations as it follows the congested South Dixie Highway.

As it turned out, Miami-Dade Transit was running a deficit and used some of the tax to close the books, as well as using some to hire new staff, pay rent, and buy furniture for their new headquarters at the Historic Overtown/Lyric Theatre station.

By the late 2000s recession, it was realized that only the 2.4-mile (3.9 km) AirportLink of the Orange Line would be funded, and after service cuts in 2008, Metrorail was running fewer trains than before the tax was passed.

[27] In response to all this, The Miami Herald published a comprehensive exposé titled "Taken For A Ride, How the transit tax went off track", detailing all of the promises that were not kept as well as what money was misspent and how.

[17] Despite the service cuts, due to the rise in energy prices and ever-increasing congestion, as well as a significant amount of residential development in the downtown area, ridership continued to grow during the 2000s, averaging well over 60,000 weekday riders throughout 2011.

These projects include Santa Clara apartments, Brownsville Transit Village,[33] and The Beacon, which is located near Historic Overtown/Lyric Theater station in Downtown Miami.

Since completion of the Airport Link in 2012, Metrorail increased its service frequency to peak headways of three and a half[40] to five[41] minutes on the shared portion of the line from Dadeland South to Earlington Heights.

Included amenities are free Wi-Fi, interior bicycle racks, improved announcement systems, digital signs and high-efficiency air conditioning units.

[43] Metrorail formerly used 136 heavy-rail cars (known as the Universal Transit Vehicle) built by the Budd Company under the name "Transit America";[44] they are identical to those used on the Baltimore Metro SubwayLink (save for the modifications made to Baltimore's cars during their refurbishment between 2002 and 2005), as the two systems were built at the same time, and the two agencies were able to save money by sharing a single order.

The Miami-Dade County Government was working with the Citizens Independent Transportation Trust (CITT) to receive money from the half-penny sur-tax approved by voters in 2002 in order to purchase new Metrorail cars.

[48] Proposals from three railcar manufacturers were reviewed, with only two of which meeting the price requirements, these being from Italy-based AnsaldoBreda and Elmira Heights, New York-based CAF USA, an American branch of the Spain-based Construcciones y Auxiliar de Ferrocarriles.

However, the contract was stalled when CAF filed a lawsuit against the transit authority, claiming that their selection of AnsladoBreda was due to the fact that the builder was willing to open a local factory in Miami-Dade County to assemble the vehicles.

[44] After reevaluating the bids from the builders, without taking local geographic preference into account, Miami-Dade reaffirmed its selection of AnsaldoBreda,[49] and in November 2012, approved a $313 million purchase of 136 new Metrorail cars from the company.

[51] By the time the custom rail-car building facility in Medley was completed in early 2016, AnsaldoBreda had been purchased by Hitachi Rail and the full rollout was pushed back to 2019, beginning gradually from 2017.

[63] Starting July 28, 2012, Metrorail increased service along shared Green and Orange Line stations from Dadeland South to Earlington Heights.

Beneath the Metrorail guideway from Brickell to Dadeland South, along the former Florida East Coast Railway right-of-way, there is a nearly contiguous 10.5 mi (17 km) bicycle and pedestrian trail known as the MetroPath (M-Path) which was built in 1984 along with the metro system.

[67] In 2014, plans were made to revamp the MetroPath as a linear park, taking after the popular High Line in New York City, by a group known as "Friends of the GreenLink.

However, after budget deficits, other uses of the tax revenue, and a downgrade of the North Corridor's funding priority to medium-low by the federal government, after 10 years only the 2.4 mile AirportLink and Orange Line remained promised and realized.

The South Link, now known as the South-Dade Transitway Corridor, is currently an under construction[78] gold standard bus rapid transit line with an expected start of revenue service in the fall of 2024.

Note the large jump in ridership starting September 2012 after the Orange Line extension to MIA opened, the largest project that came to fruition after the passing of the half-penny tax in 2002.

This lag follows Metrobus, which began to decline in 2014, amid an aging fleet and falling oil and gas prices, and posted the lowest ridership numbers in over a decade during June and July 2016.