The Sud Express (also called Surexpreso[3] Spanish: [suɾeɣsˈpɾeso] and Sud Expresso[4] Portuguese: [suðɨʃˈpɾesu]) was an overnight passenger train connecting Paris with Lisbon and Madrid, and which originally was operated by the Compagnie Internationale des Wagons-Lits and ran north of Paris to Calais.

[5] For most of the train's history, it was operated in two sections, with passengers needing to change between trainsets at the French–Spanish border because a break of gauge there prevented through operation, but from June 1973 to May 1994 the Sud Express carried through couchette cars between Paris and Lisbon (the Madrid section having been dropped in 1973), thanks to the introduction of cars with bogies (wheelsets) that could be adjusted at the border for the change of gauge.

The inaugural trip of the Sud Express took place on 21 October 1887 connecting Lisbon via Madrid to Paris in 45 hours[8] and services were extended on 4 November 1887 to Calais.

Also in 1888, the British Royal Mail launched connecting package services from Lisbon to Rio de la Plata and Brazil.

[20] A 1939 crash near Tolosa, Spain on 29 March killed, amongst others, the artist Romilly Fedden and his novelist wife Katharine Waldo Douglas.

The Portuguese government's strategic plan for transport, published in October 2011, envisaged the withdrawal of the Sud Express.

In October 2012, CP started an Intercity (later downgraded to InterRegional) service between Porto and Coimbra in order to improve the connection between the Sud Express and northern Portugal.

After 25 April 2018, the southbound Sud Express started at Hendaye (instead of Irún), due to the lack of proper certification from the new fleet of TGV 2N2 operating on the LGV SEA.

[24][25][26] In March 2021, a representative of the Spanish transport ministry said that the country may stop having night trains even after the end of the coronavirus pandemic.

[27] In November 2024, a proposal by the LIVRE Party to resume the Sud Express service between Portugal and Spain was approved.