how long it take taxi to reach Mutianyu of Great Wall from Double Tree Hilton, and taxi fare

From your hotel, take a taxi to Dongzhimen first. Then take bus line 916 Express to Huairou North Avenue. It costs CNY 12 per person. And the duration is around 70 mins. Transfer to bus line h23, h24, h35, or h36 to Mutianyu Roundabout. Afterwards, walk about 450 meters to the ticket office of the scenic area.