Serpent Cave of Gimnyeong
The legend “Gimnyeongsagul, ” about the cave Sagul in the village of East Gimnyeong in Gujwa, Jeju Island, narrates the story of Seo Ryeon, a judge during the reign of King Jungjong of Joseon, who slayed a giant serpent that lived in the cave.
To the east of Gimnyeong Village on Jeju Island was a huge cave in which lived a giant snake and the cave was called Baemgul, or Sagul, meaning Serpent Cave. Each year, the villagers held a grand ritual (keungut), offering a maiden to the snake as a sacrifice. If they did not stage the ritual, the serpent ruined all the grain fields, resulting in a famine. No noble family was willing to give up their daughter, however, and it was always a commoner’s daughter that was sacrificed, and it became impossible for commoners’ daughters to get married. Around this time a judge named Seo Ryeon was appointed to Jeju. When he heard about the serpent cave, Judge Seo was infuriated, calling the practice outrageous. He ordered a ritual to be held, offering drinks, rice cake (ttoeok) and a maiden as sacrifice, and he set out himself for the cave, accompanied by soldiers. The ritual continued for a long time and finally a gargantuan serpernt came out of the cave and after finishing the drinks and the rice cake, tried to eat up the maiden, when Judge Seo and his men attacked the snake with spears and swords and killed it. Witnessing this, the officiating shaman warned him, “Hurry and head to Jeju Fortress on your horse. No matter what happens, you must not look back.” Judge Seo whipped his horse and arrived safely outside the eastern gate of the fortress, when one of his soldiers said, “It is raining blood behind your, sir.” At this, Seo responded, “How on earth can it rain blood?” and looked back without thinking, and immediately he fell dead. The dead serpent’s blood had flowed up to the sky and turned into rain, in order to come after Seo.
A variation of this legend features a judge named Yi Sam-man, who kills the snake and upon arriving back at the courtyard of his office, turns back in relief, which kills him immediately. This incident resulted in the custom of pasting sheets of paper written with the Chinese characters 李三萬 (Yi Sam-man) to scare away snakes in spots where snakes are often observed, which was observed each year on the Day of the Snake on the first lunar month.
The legend of the Serpent Cave of Gimnyeong is transmitted as part of Yongnori (Dragon Segment), which reenacts the hunt for the giant serpent, in the grand rituals (keungut) of Jeju Island.