It passes through the Sihlsee near Einsiedeln, and then enters the Canton of Zurich, flowing through the Sihl valley (Sihltal) at the foot of the Albis, passing the Sihlwald, the largest remaining deciduous forest of the Swiss plateau, near LangnauamAlbis.
In Zurich the Sihl flows underneath the Main Station (parts of the main station are actually built below the Sihl), before joining the Limmat.