Strenuous but worth it! There is a split at 0.67km where you can go left or right. Explore both! Left is easier and right is harder, and may include steep climbs requiring a rope. There are sections where you can escape the canyon via dirt paths, and others with vertical walls on both sides. Not a place you want to be in a rain storm. If you find the trail back to the start, it comes out in someone's property with a locked gate; drop back down to the creek when you can. I made a spreadsheet of the best river traces in northern Taiwan, check it out here: https://docs.google.com/spreadsheets/d/15QNhE9z3lhwz33C6V4P11dljPzWafFGKowzTi9Wrkjg