When you feel like you need to take a rest from all that exhausting sightseeing, get some fresh air and sunshine at Yanqi Lake. Bring some nibbles and a good book ... Whatever helps you unwind!
This body of water is located in Huairou. Once you've explored everything you can at Yanqi Lake, pay a visit to nearby Mutianyu Great Wall, Huaibei International Ski, and Hongluo Temple.