關外

beyond the pass, i.e. the region north and east of Shanhai Pass 山海關|山海关[Shan1 hai3 guan1] or the region west of Jiayu Pass 嘉峪關|嘉峪关[Jia1 yu4 guan1] or both

outside / in addition / foreign / external

mountain pass / to close; to shut; to turn off / to confine; to lock (sb) up; to shut (sb in a room, a bird in a cage etc) / to concern; to involve