Jiufen is an old mountain town named after the nine families that lived in the area during the early Qing Dynasty. As an isolated village, Jiufen would receive regular shipments from town. These shipments would contain nine portions of supplies for each of the nine families in the village.
Today, Jiufen is popular for its old-style charm. Many of its features are left over from Japanese colonization during World War 2, and several tea houses, food stops, and souvenir shops have popped up since then.
My favorite stop in Jiufen is the Jiufen Teahouse, a great place to enjoy a mountainside rest. It is owned by a couple who love tea and art, and it really shows in the decor of the place. The wife also loves pottery and has a studio below the teahouse.
A Mei Teahouse is another popular stop in Jiufen, especially among Japanese visitors. Said to have inspired Miyazaki during his creation of Spirited Away, the teahouse and surrounding street is bathed in red lanterns and memorabilia from the movie. Though this is likely just clever marketing (I've heard Miyazaki denied such claims of inspiration), the decor makes for a beautiful, scenic destination.