The Middle Sea is a long, narrow, salt sea separating the western lands from the eastern. It stretches nearly 1300 miles from north to south, and slightly less than 200 miles across at its widest point. The Middle Sea is empties into the northern ocean, a 150 mile wide mouth that freezes over during the coldest winters. The sea is shallow, less than 500 feet deep at the deepest point. The water is always cold, due to deep currents of frigid northern water flowing south along the seabed, while warmer surface water flows north.
Coastlines along the middle sea tend to be mud flats or bluffs eroded by the tides. The fishing is good, and in most places one can’t sail a day along the coast without passing at least one village. Springtime brings fog along this coast, which burns off by summer. Low islands in the sea facilitate trade sailing directly east and west, so that merchants don’s have to sail the length of the coast.
There was not always a Middle Sea, though. Prior to 700 or so years ago, the region was dry land, a plain with a mighty river flowing from southern mountains to the northern seas. This was the original homeland of humanity, and their chief city, Carcossa, sat astride the river’s midpoint.
The priest-kings of Carcossa, though, grew arrogant, and sought to make themselves gods. The gods struck them down, destroying Carcossa and flooding the plain, creating the Middle Sea. Adventurers still dive for artifacts of this lost kingdom.