Su-ao Cold Spring is in Suao village, in the south of Yilan County. It is rich in rare mineral-spring resources besides the one in Venice of Italy in the world. Su-ao Cold Springs was found in 1928. In earlier days, Su-ao is famous for its sweet red bean jelly and its marble soda, both of which were made with the carbonated spring water. The cold springs of Su-ao produce colorless, odorless bicarbonate water at a temperature of 22 degrees Celsius. And it is the only calcium carbonate spring in Taipei.