how far is the Jinshanling from Beijing and how long is the travel time?

If you go there on weekends and holidays from April to November, the Toursim Special Line is the best choice, which will take you about 2 hours to reach the attraction. It is about 130 km from Beijing to the great wall. The bus starts at 07:30 from Dongzhimen Bus Station and go back to Beijing at 14:30.
If you go there at other time, you can go to Dongzhimen Bus Station to take bus for Chengde and get off the bus at Bakeshiyinghualougou and then you can find mini-buses to reach the attraction.
Jinshanling is farther than Mutianyu. In my opinion, Mutianyu is suggested, because the scenery is beautiful and the transportation is more convenient than other sections.