C8 : Atocha – Villalba – Cercedilla
The Green C8 cercanias line runs up to the north-west tip of Madrid from Atocha Station. You can see all the stations on the schematic map below :
c9 : Cercedilla – Cotos.
From Cercedilla, you can change onto the C9 line. There is only one intermediary stop : Puerto de Navacerrada.