북한산 철모바위 투구바위(Bukhansan Cheolmo Rock, Tugoo Rock)
Iron helmet(Cheolmo) refers to helmets made of iron mainly used by modern soldiers, and pitching(Tugo) refers to helmets worn by knights in the past.
Bukhansan Cheolmo Rock and Tugobawi Rock are very close. The picture above is Cheolmobawi Rock and the below is Tugubawi Rock.