Cave is located inside Hallim Park, so you have to pay the park entrance of 15.000 Won (Adult, 1000 Won coupon for snack/souvenir) to enter the cave. We spent 4 hours inside this lovely park, but the cave alone is SO impressive that it's worth the money alone. Don't miss the info booth before the first cave entrance, explaining some cool details why this cave is geological unique, if you're into it. If not: just go inside and be impressed and enjoy the cool air and some drops of water falling from the ceiling... Cave consists of 3 parts. Just follow the route and enjoy.