CP — Comboios de Portugal, EPE (CP; English: Trains of Portugal) is a state-owned company which operates freight and passenger trains in Portugal. Before June 2009, CP stood for Caminhos de Ferro Portugueses (English: Portuguese Railways) although the company has been using its current designation as a brand name since 2004.

On 28 October 1856 the first railway line was inaugurated in Portugal, between Lisbon and Carregado: the Companhia dos Caminhos de Ferro Portugueses was born. The network was gradually expanded both south of the Tagus and to the north of the country, as well as in the metropolitan areas of Lisbon and Oporto and to Spain. During the second half of the 20th century, much of CP's rolling stock was built in Portugal by Sorefame - notably carriages with stainless steel bodywork.

Gradually, electrification was put in place for a little less than half the network. In 1975, the company was nationalized and its name was shortened to CP, A plan to finally connect all the district capitals by a fully electrified double line will be implemented from 2010. Part of this plan is based on the Swiss Rail 2000 model.

Portugal ⁱ/ˈpɔrtʃʉɡəl/ (Portuguese: Portugal, IPA: [puɾtuˈɣaɫ]), officially the Portuguese Republic (Portuguese: República Portuguesa) is a country situated in southwestern Europe on the Iberian Peninsula . Portugal is the westernmost country of mainland Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the Azores and Madeira are part of Portugal. The country is named after its second largest city, Porto, whose Latin name was Portus Cale.

The land within the borders of the current Portuguese Republic has been continuously settled since prehistoric times: occupied by Celts like the Gallaeci and the Lusitanians, integrated into the Roman Republic and later settled by Germanic peoples such as the Suebi, Swabians, Vandals and the Visigoths. In the 8th century most of the Iberian Peninsula was conquered by Moorish invaders professing Islam, which were later expelled by the Knights Templar under the Order of Christ. During the Christian Reconquista, Portugal established itself as an independent kingdom from León in 1139, claiming to be the oldest European nation state.