LGV Sud Europe Atlantique

The LGV Sud Europe Atlantique (LGV SEA, English: South Europe Atlantic High Speed Rail Line), also known as the LGV Sud-Ouest or officially named LGV L'Océane by SNCF since April 2016, is a high-speed railway line between Tours and Bordeaux, in France. It is used by TGV inOui and Ouigo trains operated by SNCF. It is an extension of the southern arm of the LGV Atlantique, with the western extension being LGV Bretagne-Pays de la Loire. Both extensions to the high-speed line were inaugurated on 28 February 2017, with services beginning on 2 July 2017. The line, which was at the time the biggest European railway construction project, was built by the LISEA consortium, which owns and maintains the line until 2061 and charges tolls to train companies. Trains on this line depart Paris from Gare Montparnasse.

With trains operating at speeds of up to 320 km/h (200 mph), the line allows travelers to connect Paris to Bordeaux in approximately two hours, representing a time saving of nearly one hour compared to the classic line. Extensions from Bordeaux to Spain (LGV Bordeaux-Espagne) and to Toulouse (LGV Bordeaux - Toulouse) are under consideration, with preliminary work for the latter having begun in May 2024 and the first service expected in 2032.

The financing, construction, operation, and maintenance of this line were conceded to a private company, LISEA, for a period from 2011 to 2061, making it the first high-speed line in France to be built under such a concession model.