Freeway No. 6 (also called Shuishalian Freeway or Central East-West Freeway) is a freeway between Wufeng, Taichung and Puli, Nantou, and all of the main line was already open to traffic on March 21, 2009. The freeway runs parallel with Provincial Highway 14 for most of its length.
Its construction was begun on March 25, 2004. On January 27, 2008, the main line between Ailan IC and Puli terminal was open to traffic. Then, the main line between Wufeng JCT and East Caotun IC, and the East Caotun connection way were open to traffic on December 27, 2008. The other part of main line between east Caotun IC and Ailan IC was already open to traffic on March 21, 2009. Afterwards, Guoxing IC was open to traffic on October 22, 2009. Then, Jiuzheng IC was open to traffic on January 31, 2011. Beishan IC was completed on November 21, 2013.