Mudflats are areas of land that are submerged under seawater during high tide that become exposed as wetlands during low tide. Covering about 2.5% of South Korea's total land area, these mudflats are rich in biodiversity and have been recognized for their value by being inscribed as a UNESCO World Heritage in 2021. Additionally, the "Long Boards Used for Moving around a Mud Flat" fishery, the "Muan-Sinan Mudflat Octopus Bare-handed Fishing," and the "Hadong-Gwangyang Cockle Hand Rake Fishery" have been designated as National Important Fishery Heritage Nos. 2, 6, and 7, respectively.

Let's explore some artifacts related to mudflats. To the far right and at the bottom, you can see wooden boards resembling skis, displayed as exhibit #12, "Long Boards Used for Moving around a Mud Flat." These boards were used for moving around on mudflats while harvesting clams or transporting the day’s catch. The main distinctive feature is one end of the long plank being raised like that of a ski.

The next artifact is "Wooden Bowl and Oyster-Shucker," displayed as exhibit #11. The wooden bowl, or 'gulhamji,' is a carved-out log used as a workbench for shucking oysters. The tool hanging inside, the oyster-shucker or 'josae,' was used for scraping off oysters attached to rocks or stones and for laying out oyster shells. The large hook on the top part was used to crack or break oyster shells, and the small blade at the handle's end was used to extract the oysters from their shells.

Lastly, we have the "Hand Dredge and Hand Net" used around the lower Seomjin River for cockle fishing. exhibit #1, the "Hand Dredge," was used to scrape the riverbed to collect cockles. exhibit #2, the "Hand Net," was used for gathering cockles and rinsing off the mud.