Estación Once

Once de Septiembre
Station building, c.1900.
Location	Av. Pueyrredón and B. Mitre Buenos Aires Argentina
Owned by	Government of Argentina
Operated by	Trenes Argentinos (Sarmiento Line) Ferrobaires (Long distance services)
Platforms	7
Tracks	8
Connections	Underground
History
Opened	20 December 1882 (1882-12-20)
Electrified	Third rail

Once railway station (Spanish: formally Estación Once de Septiembre (11th of September Station), informally estación Once (Eleven Station)), IPA: [ˈonse]) is a large railway terminus in central Buenos Aires, Argentina in the barrio of Balvanera.

The station, inaugurated on December 20, 1882, is located in the barrio of Balvanera immediately north of Plaza Miserere, a large public square. The station is named after the September 11, 1852, rebellion of Buenos Aires against the Federal government of General Justo José de Urquiza. Coincidentally President Domingo Faustino Sarmiento also died on September 11 (1888), but contrary to popular belief in Argentina, this is not the date commemorated by the station's name.

The Buenos Aires Western Railway was the first railway line of Argentina, having been opened in August 1857 joining Del Parque station (where currently Plaza Lavalle is located) to Flores district of Buenos Aires through 10-km. length. The first intermediate stop was named "Once de Septiembre".

That first Once de Septiembre station was a modest building made of wood and placed on Bartolomé Mitre street. It had only one platform and some warehouses to store wood and other materials. The increasing growth of Buenos Aires as a consequence of mass immigration to Argentina meant the closure of Del Parque railway station, therefore Once became the terminus. A new building was built for that purpose, which was inaugurated on January 1, 1883. The building was made of wood.