19.9 km. According to Baidu map, the whole journey is about 19.9 km, and the bus ride time is about 59 minutes. Get on the bus at the west exit of Afang 1st Road, get off at Sanqiao Station by bus No.725, walk for 230m, get off at Wulukou Station, change to walk for 70m, get on at Wulukou Station, and get off at Heping Gate Station of Metro Line 4, and you can reach your destination.