This statement was an awakening for Su: the Alishan Forest Railway gains 2,421 m in elevation between its starting point in Chiayi (30 m) and its highest point at Zhushan (2,451 m), an altitude gain even greater that that of the world's highest railroad, China's Qing-Zang Railway (2,828-5,072 m).
一語點醒夢中人，蘇昭旭驚覺阿里山森鐵從起站嘉義（海拔 30 公尺）到最高點祝山（海拔 2,451 公尺），海拔落差達 2,421 公尺，比全世界海拔最高的鐵道──中國青藏鐵路（2,828 ∼ 5,072 公尺）的落差還要大。