London-Beijing-Hangzhou-Beijing -North Korea

Dear All,

Our fly is from London-Uk to Hangzhou , It is not a direct fly and would have 3 hours in Beijing for a transfer to Hangzhou.In Hangzhou will be from 25.12.2018-5p.m to 28.12.2018-9.p.m , when is our fly back to Bejing . We will have a night in Beijing and then 29.12.2018 -5.30 p.m going to North korea , where will stay until 03.01.2019.We will be back to China on 04.01.2018 , sleep one night and on 05.01.2019 going back to London.Please advise what type of visa we nee.Thank you in advance.