This is the legend of Wooly Swamp:

A psychological crazed rich man was living in a swamp. He bottled up his money and put it in the quicksand just outside his house. And every full moon, the money in the bottles would rise and he would dig it up, throw it on the floor, and roll in it. Then one night, a group of thugs decided they would beat the old man, throw his body into the quicksand, then steal his money. So they waited until the man dug up his money, walked into his house beat him up and threw him in the quicksand. They took all the money and ran outside when they realized they were sinking below the ground in quicksand. And as they were screaming for help, they could hear the old man laughing. To this day, if 당신 go to Wooly Swamp on a full moon, 당신 can still hear the men screaming and the old man laughing, because there is a quicksand spot that never dries up.