The Castrovin Sea is a large, land-locked body of water that begins near the ancient realm of Iobaria in northwestern Casmaron and stretches thousands of miles eastward. It borders the lost kingdoms of Ninshabur and Kaskkari in its western and southwestern reaches, the mighty Kelesh Empire to the south, and fabulous Kaladay to the northeast. Strange island nations can be found along its coast. At least in its northwestern regions, the Castrovin is harsh and choppy, making it difficult to navigate. Sea traffic is generally limited to small fishing vessels which stay close to the coastline. The Castrovin Sea has a generally tempering effect on the climate of Casmaron, increasing rainfall and moderating temperatures along its shores.
The Castrovin Sea is home to noticeably smaller numbers of fish and mundane wildlife than other seas and oceans, and is entirely bereft of cetaceans, limiting the size of the fishing industry. However, it is home to large populations of sturgeon, which are harvested for their valuable roe, and to numerous varieties of turtle, which are hunted for their meat and shells. The eastern Castrovin Sea is also populated by numerous sea cats, large prides of which can be spotted lounging on its stacks and beaches in the summer.
Sapient natives of the sea include reclusive locathah, who sometimes emerge at a specific sea stack in the northwestern part of the sea to trade with passing ships, and more hostile races such as merrows and scrags.
The Castrovin Sea is the main waterway for trade for the nations along its shores, and countless merchantmen from Kelesh and other exotic locales make their way along its coasts. This in turn attracts pirates who prey upon the merchants, countered by naval ships of the Empire of Kelesh. All but the most foolhardy sailors, however, avoid sailing into the deeper waters. The central Castrovin Sea is plagued by terrible storms and by a maze of rocky islets, juts of volcanic rocks and sea stacks like Casador's Maw, Citadel Allatro, and the Pillars of Trajheir, collectively called the Razored Labyrinth, which make navigation difficult and dangerous. These small outcroppings of land are often the domain of locathah tribes and pale-scaled merrows, who exploit the connections of these islets to deep tunnels to the Darklands.
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