Pick up the bus back to Chengdu a little bit downhill of the tourist center in parking lot. "Chengdu" will probably NOT be written in pinyin so you will have to ask the driver. The Chengdu bus is usually closest to the top of the parking lot though and does not leave until it is full. Cost back is ¥20 and may not bring you to the bus station you want to be at in Chengdu.
Another alternative is to take the brand new high speed rail link back to Chengdu. It is much faster and convenient than the bus which cuts your travel time in half and delivers you in first class conditions to the North Train Station. A bargain price of only 15/20 Yuan. A taxi to the train station from the Qingchengshan parking lot will cost around 20 Yuan.
You may want to visit Dujiangyan Irrigation System after a trek up the mountain, which is the last stop for bus number 101 and leaves from the Qingchengshan parking lot. It costs two and a half Yuan and is just a forty-five minute bus ride away. The high speed train bound for Chengdu also leaves from Dujiangyan.
