This incredibly beautiful trail, accessible from the town of Yuli, is inside the Yushan National Park and actually part of the much longer Batongguan trail, which will take you all the way over to Dongpu.
That is a 7 day hike, but if you are looking for something a little shorter, then it is well worth hiking the first 13.5km of this trail to the Walimi Cabin. The trail is very gentle and visually stunning.
On the way to Walami Cabin, you will pass over several suspension bridges, past steep cliffs and plunging waterfalls, all to the soundtrack of thousands of cicadas and the odd macaque crashing through the trees. There is a lovely viewing platform at the end of the 13km that provides (weather permitting) a glimpse of the majestic peaks of Yushan.
A mountain entry permit must be applied for in advance. Bring your own sleeping bag/mat if planning on spending the night in the cabin.