Yilan City
The route of the highway begins in the west at Dongshi District in Taichung. The highway originally continued up into the Central Mountain Range following the Dajia River valley through the townships of Guguan (谷關) and Cingshan (青山). However, the section between Guguan and Lishan is permanently closed to non-residents due to earthquake and typhoon damage. At Lishan there is a branch that heads north to Yilan City. Passing through the mountains it reaches Dayuling (大禹嶺) which is the highest point of the route. Here another branch of the highway runs south from Dayuling to Puli via Wuling (武嶺). Continuing east from Dayuling the highway route now begins its descent into the Taroko National Park. It passes through Guanyuan (關原), Cih-en (慈恩), Luoshao (洛韶) and before entering Taroko Gorge. After the gorge the route then connects with the eastern coastal Su'ao-Hualien Highway.