Various volcanic rocks, formed during early volcanic eruptions, are well-preserved along Dodong Seaside Walkway. The basaltic agglomerate formation is characterized by lava flows, clinkers, and hyaloclastite deposits that have accumulated repeatedly over time. In addition, various of other geological phenomena including dikes (formed when magma intruded into the existing cracks of basaltic agglomerates), caves (result of differential erosion), vesicles (cavities in rocks formed by the expansion of a bubble of gas that was trapped inside lava), amygdules (secondary minerals within vesicles). Tafoni, small cave-like features found in rocks caused by physical and chemical weathering, are observed in certain areas of the walkway. Tafoni, found in Jeodong, were formed by saline solutions that seeped into cracks in the rocks, exposure to direct sunlight, or wind.