Best way from Capital Airport and hotel 161 Wangfujing hotel.

Upon landing, take airport shuttle bus line 13, get off at Jinbao Street (Regent Hotel) first. The ticket fare is CNY 24 per person. Then walk north along South Dongsi Street around 900 yards (820 meters) to find the hotel.
From the hotel to the mountain, take subway line 6 from Dongsi to Ping'anli and transfer to line 4 to Beigongmen, Exit A. After arriving, take a taxi to the destination. The cab fare is about CNY 30 in day time.

Thanks so much Catalina