The Light Rail Transit Line 1, commonly referred to as LRT Line 1 or LRT-1, is a light rapid transit system line in Metro Manila, Philippines, operated by Light Rail Manila Corporation (LRMC) and owned by the Light Rail Transit Authority (LRTA) as part of the Manila Light Rail Transit System. Originally referred to as Metrorail and the Yellow Line, LRT Line 1 was reclassified to be the Green Line in 2012. It travels in a general north–south direction from to , and then east–west from Monumento to Fernando Poe Jr.. Currently, the line consists of 20 stations and runs on of fully elevated route. Although it has the characteristics of light rail, such as with the type of rolling stock used, it is more akin to a rapid transit system owing to its total grade separation and high passenger throughput.
A 1977 study conducted by Freeman Fox and Associates suggested a street-level railway in Manila but the government revised this recommendation to an elevated system. In 1980, President Ferdinand Marcos created the LRTA and construction of the line began the following year. With the opening of its first segment in 1984, it became the first rapid transit service in Southeast Asia.

The line was the busiest among Metro Manila's three rapid transit lines from 2016 to 2020, after Lines 3 and 2. It served 216,667 passengers on average in 2022, making it the second-busiest.

The line is integrated with the public transit system in Metro Manila, and passengers also take various forms of road-based public transport, such as buses and jeepneys, to and from a station to reach their intended destination. Although the line aimed to reduce traffic congestion and travel times in Metro Manila, the transportation system has only been partially successful due to the rising number of motor vehicles and rapid urbanization. Expanding the network's revenue line to accommodate more passengers, through extension projects, is set on resolving this problem.

Route
The line is predominantly aligned to the path of Taft Avenue (Radial Road 2) which was chosen largely due to its straight course. Later on, as Taft Avenue ends, it shifts to Rizal Avenue and Rizal Avenue Extension (Radial Road 9) then turning right on EDSA before ending at the corner of North and West Avenues and EDSA. The line links the cities of Quezon City, Caloocan, Manila, and Pasay, with the upcoming stations passing through the cities of Parañaque, Las Piñas, and Bacoor in Cavite.
Stations
The line serves 20 stations along its route. A twenty-first station is yet to be constructed. Eight stations which are part of the south extension are also set to be constructed south of Baclaran. station in Caloocan was previously proposed during the construction of the northern extension located between and , becoming a bargaining object during the entire extension line's construction in the jurisdiction of Caloocan. However, the planned Malvar station was completely shelved by the Aquino administration.
Three stations serve as connecting stations between other lines in the metro. is indirectly connected to the of the LRT Line 2 through a covered walkway; is immediately above its PNR Metro Commuter Line counterpart; and is connected to the station via a covered walkway. No stations are connected to other rapid transit lines within the paid areas, though that is set to change when the North Triangle Common Station, which has interchanges to MRT Line 3 and MRT Line 7, opens in 2023.
Operations and services
The line operates from 4:30 a.m. PST (UTC+8) until 10:15 p.m. on weekdays, and 5:00 a.m. until 9:45 p.m on weekends and holidays. It operates almost every day of the year unless otherwise announced. Special schedules are announced via the PA system in every station and also in newspapers and other mass media. During Holy Week, a public holiday in the Philippines, the rail line is closed for annual maintenance, owing to fewer commuters and traffic around the metro. Normal operation resumes after Easter Sunday. During the Christmas and year-end holidays, the operating hours of the line are shortened due to the low ridership of the line during the holidays.





