The fossilized shell graveyard, dating back approximately 40 million years according to geological calculations, was once a large freshwater swamp teeming with life, particularly with countless freshwater snails measuring around 2 centimeters in size. As changes occurred on the Earth's surface, seawater flooded the swamp, causing the calcium carbonate in the seawater to bond with the underwater shells, forming a solid mass. This eventually transformed into a hard rock formation known as Shelly Limestone, which is about 40 centimeters thick. As the land was uplifted, these fascinating fossil remains became exposed for all to see.