Hello, how long going bus from Beijing airport to Baidahe city? in June? or sould i take subway or train? Thanks

Hi, Maria. I have no idea about Baidahe City, would you mind confirm it?
Do you mean Beidaihe, in Qinhuangdao city?
If so, you can take the airport direct shuttle bus for Qinhuangdao city in about four hours. Upon reaching, you can walk to the Qinhuangdao railway station to find the local public bus line 34 to reach Qinhuangdao directly.