travel to central Beijing

I found that my hotel, Garden International, is in the Miyun district. This is the hotel that is part of the RCI network for timeshare exchanges. I just found this is as much as 60 minutes from the center (Tiananmen Square area). I can not find Miyun on the subway map. How will I get to central, Tiananenmen area? Sincerely, Carolyn Gallaher