u/Holiday-Coke-Bottle

I will be flying to Beijing for 4.5 full days only in 2 weeks. A morning trip to the wall is already using almost a full day (Huanghuacheng or Jinshanling). Are there any trips to see China's nature close to Beijing I should book/get a ride to? I am so much into wildlife and nature in every country. Also any other tips for the city itself, e.g. best museums, parks, culture? Please let me know whatever comes into your mind for a short trip like mine. (+ Which Chinese cities/landscapes I should definitely go to next time)