Korea's National Treasure No. 285, the Bangudae Petroglyphs, are located mainly on flat vertical rock faces around 8m wide and around 5m high on steep cliffs on the riverside of the Daegokcheon stream, a branch of the Taehwa River, which runs eastward and joins the Donghae at Ulsan. The surrounding ten rock faces have a small number of engravings as well. The rocks consist of shale and hornfels oriented toward the north and they shine for a while at sunset. As an overhanging cliff they are in the structure of a rock shelter. From Wikipedia
