The Third Ring was very large and contained a great number of Cultivators. Most organized into groups of three or perhaps five to go hunting Sea Demons in various regions of the Third Ring. To encounter a Sea Demon was a lucky break in and of itself. Of course, there were some powerful Sea Demons who could also bring incredible disaster.
There were even some areas within the Third Ring that were specially noted in jade slip maps. Anyone who wanted to enter such areas had to prepare special items ahead of time.
Furthermore, there was one particular city in the Third Ring called Seahold that had been established jointly by the three Sects, which made it convenient for Cultivators to trade for supplies. The city was enormous, and towered up above the surface of the water like a huge fortress. It was covered with shocking spell formations that had protected it for countless years against the attacks of Sea Demons.