The route continues eastbound towards the rural township of Fenyuan and enters Nantou County.

In Ren'ai the highway passes through Wushe and Lushan Hot Spring.

After passing through Lushan, the highway turns into a narrow 1-lane road before ending at Tunyuan (Tnpara), the western entrance of Nenggao Cross-ridge Historic Trail (能高越嶺古道), a historic route connecting between Nantou and Hualien.

The stretch between Lushan and Tunyuan, as well as the Nenggao Cross-ridge Historic Trail, require special permits to access.

A planned extension of the highway to Xiulin, Hualien was unfinished due to environmental and economic concerns.