[1] The township comprises seven villages: Guangcheng, Liyutan, Longteng, Shengxing, Shuanghu, Shuangtan and Xihu.
The township is part of Miaoli County Constituency I electoral district for Legislative Yuan.
Initially, the Sanyi area produced timber and hides.
[2] At one point, over 80% of local families were employed in wood carving.
[3] At the end of the 20th century Sanyi began developing a tourist industry.