sentences:  At Tøyen, the line splits into the Lambertseter Line and the Grorud Line.The tunnel is the bottleneck of the metro, allowing 24 trains per hour in each direction west of Stortinget, and 28 east of Stortinget.The Common Tunnel is a long double track rapid transit line running east from Majorstuen to Tøyen and onwards to Brynseng.