This is Korean noodles made with seafood.
Scallops, prawns, shells, mussels are put into boiling.
The taste is slightly salty and rich savory(umami).
The Yellow Sea Seafood Kalguksu is the most famous noodle house in Ul lang-ri, Yeongjong-do, Incheon, Korea.
The price is a little expensive at 10,000 won per person. However, I do not think it is a waste because there are a lot of quantity.
See Google Maps for directions.