이란 선 (Yilan Line Taiwan Railways, 台鐵 宜蘭線 )
Trains traveling along the Yilan Line section of the main line have varying destinations with through service on connecting lines. Many trains heading west to Taipei terminate after Taipei Main Station at Shulin Station. Trains traveling east to Yilan from Taipei may terminate within Yilan or at Su'ao, or may change to the North Link Line at Su'aoxin and terminate at Hualien or Taitung.
Trains bound for Pingxi travel along the Yilan Line for part of the their journey before branching onto the Pingxi Line.