Answered by Danny from Iraq | Aug. 12, 2015 03:09
David, you need to reach Xizhazi Village first and then walk around 1 to 1.5 hours to reach Zhenbei Tower. You should take no.916 Express from Beijing to Huanrou Yingbin Road and then change no.862 bus to reach Yu Jia Yuan Station. There you can change direct bus to Xizhazi Village. It departs at 11:30. If you fail to catch the bus, then you can hire a van to take you to the village. Better find some other travelers to share the fee for hiring the van.
Travellers usually stay at the farm houses in the village for a night and then climb the wall in the early morning next day. If you are unfamilar with the roads, you might ask the house owners to guide you.