This route follows the Appalachian Trail in the Hundred Mile Wilderness.  Start at the Gulf Hagas TH and follow the AT to White Cap Mtn, then return the same way.  About 22 miles round trip.

Cascade Mountain Trail is a popular hiking trail to access Porter Mountain and Cascade Mountain. The trail is exposed and steep with easy rock scrambles along the way. Hikers will be treated to amazing views and a waterfall on their way up. The summits can be crowded during the summer months.

The trail is a popular destination for Lake Placid hikers and ski enthusiasts. Check the weather before going as cold conditions and sudden weather changes are frequent.

The trailhead can be reached from Route 73 before reaching Cascade Lakes.

This is an out & back route to Jiaming Lake, with summits Xiangyang Mountain and Sancha Mountain along the way.  It is around 15km each way.  This article describes the route & area:

https://www.taiwannews.com.tw/en/news/3135201

Christof Teuscher submitted the route: