Trambesòs is a tram–light rail system in the Spanish autonomous community of Catalonia that links the Barcelona district of Sant Martí with Badalona and Sant Adrià de Besòs. Its name comes from the union of the words "tram", an abbreviation of the Catalan word for "tram" (tramvia), and "Besòs", the name of an area in the north of the Barcelonès region dominated by the Besòs River.

Badalona is a municipality in Barcelonès county, in Catalonia (Spain). It is located to the north east of Barcelona, on the left bank of the Besòs River and on the Mediterranean Sea, in the Barcelona metropolitan area. By population, it is the third largest city in Catalonia and the twenty-third in Spain. It became a city in 1897.