sarrià station is the junction point between barcelona metro line l6 to reina elisenda, and the metro del vallès lines to sant cugat, terrassa and sabadell. during off-peak periods it is served by lines l6, s1 and s2, all of which run through to plaça de catalunya station. in peak periods additional through service is provide by lines s5 and s55, but in order to provide capacity for this in the tunnel to plaça de catalunya, many peak l6 service simply shuttle between reina elisenda and sarrià.