Hi there, I'm planning to go to Bukhansan in May where I think the weather is good due to my friend's request, we've been through some adventures lately with Josua Tree
and it's really fun they are very good like you won't regret you had them in company, anyways you can check Bukhansan out and see if you like. And hey if you ever came close to CA feel free to contact Josua Tree
you won't regret it I promise. Hope this helps.