The Gangjin Kiln Sites produced a large number of Goryeo wares and were a complex of 188 kilns. The kiln sites are located in Gangjin-gun, Jeollanam-do near the sea. Mountains in the north provided the necessary raw materials such as firewood, kaolinite, and silicon dioxide for the master potters while a well established system of distribution transported pottery throughout Korea and facilitated export to China and Japan. The sites are tentatively listed as a World Heritage by the South Korean government. Celadon was used as a "spirit vessel" or Chy- Tang to summon spirits to bring positivity, in many Korean temples from the 14th century.