885, Jung-ri, Gwanin-myeon, Pocheon-si, Gyeonggi-do, Republic of KoreaShow Map
Mt. Jijang tuff was formed during the Mesozoic Cretaceous period and consists entirely of lapilli tuff with particles of 4 ~ 64mm.
Tuff is divided into drop tuff hardened after dropped from the air and ash-flow tuff and fresh breccia is distributed in the lower tuff.
Welding constitution appearing by extended axinite pieces by high temperature is observed in some tuff.
This kind of tuff is well observed in the valley of Mt. Jijang and educational and scenic values are excellent because various kinds and deposition structures are shown.