Line D of the Buenos Aires Underground runs from Catedral to Congreso de Tucumán. The line opened on 3 June 1937 and has been expanded to the north several times. The line is currently 11 km long and has 16 stations, while running approximately parallel to the city's coastline.

The Buenos Aires Underground, locally known as Subte, is a rapid transit system that serves the area of the city of Buenos Aires, Argentina. The first section of this network opened in 1913, making it the 13th earliest subway network in the world and the first underground railway in Latin America, the Southern Hemisphere, and the Spanish-speaking world, with the Madrid Metro opening five years later, in 1919. As of 2023, Buenos Aires is the only Argentine city with a metro system.