Real Madrid Castilla Club de Fútbol is a Spanish football team that plays in Primera Federación – Group 1. It is Real Madrid's reserve team. They play their home games at the Alfredo Di Stéfano Stadium with a capacity of 6,000 seats.
Reserve teams in Spain play in the same league system as their senior team rather than a separate league. Reserve teams, however, cannot play in the same division as their senior team. Therefore, Real Madrid Castilla are ineligible for promotion to the La Liga as long as Real Madrid plays there. From Wikipedia
