The area where Unjusa Temple of Hwasun is located, is composed of the Cretaceous tuff. The outcroppings are of lapilli tuff with well-developed layerings. The pyroclastic materials and bedding planes indicate that the site was formed at the mouth of a volcano. In addition, the bedding planes provide information on volcanic activities and period of dormancy of the time. At the temple, outcrop exposures, few meters high, can be observed in the cliff. Several small and big buddha statues are positioned in front of the cliff, which add an air of mysticism. All the stone works found in Unjusa Temple including the buddha statues were made of tuff found in the area during Goryeo period.