Formation of the cold springs requires abundant underground water reserves and a rich lime stone stratum. Suao fits these requirements because of the rich rainfalls she receives and the local thick and solid lime stone deposits, hence these springs are one of the 3 rarest cold spring sites in the world. Located near the intersection of Jhongshan Road and Cold Springs Road, the Suao Cold Springs were discovered by the Japanese in 1928. Currently there are two cold springs bath locations: one at Suao Cold Springs Area sporting men/women outdoors public pool and private tubs, and a second located near the Alishe Bridge featuring a children's water activities area and a men and women's pool. Admission is free to locals, while a small cleaning fee is charged to visitors from outside of Yilan. When you first plunge into the cold springs, you will be shivering cold, however after a short while, your body warms up and becomes covered with natural bubbles which constantly rise from underground. It is like soaking in a sugar-free soda - a unique and fun experience. The springs' medicinal properties are said to be good for skin disease and stomach illness. Here, the water which has a high carbonation content stays at 22 degrees Celsius year round. This resource was put to use as early as the Japanese Occupation period via the establishment of a cold springs soda factory on the site. The cold springs soda, known as the ''Lemonade'', along with ''Yanggeng (a sort of bean-jelly bar)'' made from cold springs water are 2 local delicacies.