noun, noun or participle which takes 'suru'
mountain hiking; walking in the mountains
Refers to the activity of hiking or walking in mountainous areas. Can be used as a noun or with する to mean 'to go mountain hiking'.
週末に友人と山行を楽しんだ。
I enjoyed mountain hiking with a friend over the weekend.
来月、北アルプスに山行する予定
I plan to go hiking in the Northern Alps next month.