Rayo Vallecano de Madrid, S.A.D. (Spanish pronunciation: [ˈraʝo βaʎeˈkano ðe maˈðɾið]), often abbreviated to Rayo, is a Spanish football team based in Madrid, in the neighbourhood of Vallecas. Rayo was founded on 29 May 1924, and currently compete in Segunda Division following relegation from La Liga. Home games are held at the 14,708-seater Campo de Futbol de Vallecas stadium.
Rayo has competed in one European competition, the UEFA Cup in the 2000–01 season. The club made it to the quarter-finals before losing to fellow Spanish club Alaves 4–2 on aggregate.
Rayo Vallecano saw the light of day on 29 May 1924 in the hometown of Prudencia Priego, wife of the club's first president Julian Huerta. Greatly inspired by River Plate (a Football club from Argentina), in 1949, after an agreement with Atletico Madrid, a red diagonal stripe was added to the team's kit, and the club reached Tercera Division for the first time in its history.
One of the perennial yo-yo clubs of Spanish football, and always in the shadow of the two biggest clubs in the city (Real Madrid and Atletico Madrid), Rayo Vallecano spent many years during the 1980s and 1990s moving back and forth between La Liga and Segunda Division.