@slowwalker, The beach in Mohang Port Of Byeonsan Area, really wondering to me. I have doubt how was created those type rocks & stones. In fact I accept your argument as you mentioned here. Best geographical location to must visit.

There were the patterns of the fishbones on the surface of the rocks

Yep it's evidence of the lava heat. Absolutely huge thanks to you showing my favorite subject of find geographical location around the world.