According to the results of an analysis of animal bones discovered in a shell midden in Ulsan and widespread along the southeastern coasts and of research on Ulsan Bay's archaeological environment, the site dates from 6,000 to 1,000 BC. Many relics related to the themes of the rock art were found at Neolithic sites, include deer pattern pottery, net pattern pottery and shell mask discovered in the Dongsam-dong Shell Midden in Busan, a figure with human faces in Osan-ri in Yangyang, a small clay wild pig excavated from the shell midden on Yokjido island of Tongyeong, the clay figure of a woman in Sinam-ri in Ulsan, and a small clay seal excavated from the shell midden in Sejuk-ri, Ulsan. Furthermore, a boat was excavated from the shell midden in Bibong-ri, Changnyeong, and during the Hwangseong-dong site excavation research project conducted by the Korea Archaeology and Art History Research Institute a whale bone stuck with a harpoon was found, which empirically proves whaling.