one of the unique aspect of south korea's fauna environment is that they have a demilitarized zone. demilitarized zone has been designated as a 2 km zone (4 km in total) between north and south, centered on the mdl (military demarcation line) since the korean war. the southern boundary of the demilitarized zone is the sll (southern limit line) and the northern boundary is the nll (northern limit line). for over 60 years, the area has been strictly forbidden for public activities, preserving natural ecosystems, and attracting attention as asia's largest protected area.