Siheung Mine was dug halfway up Gahaksan Mountain in Gyeonggi-do Province in 1912 to provide Japan with mineral resources. Since the mine was closed down in 1972, it was used to store shrimp sauce and has been practically abandoned since then. Then the mine was reborn as the Gwangmyeong Cave Theme Park in 2011. Let's descend into the depth of Gwangmyeong Cave, which draws more than 1.5 million tourists annually.