The project consists of seven kilometres of new underground metro, which constitutes the future Madrid Metro line 11 extension between Conde Casal station and Plaza Elíptica station. The project also comprises five underground metro stations: Comillas, Madrid Rio, Palos de la Frontera, Atocha Renfe and Conde de Casal. The first three stations are new ones, while Atocha Renfe and Conde de Casal are existing underground metro stations that will be refurbished.