The Gulf of Teneucia (pronounced teh-NOO-see-ah) is a body of water in northern Hellea. The gulf almost completely separates the peninsula from the north, with a stretch of land west of the gulf only 65 miles wide at the narrowest, where the Greenwall makes its way south from the Sentinel Peaks, connecting the two lands. Though not as large as the Sea of Ersas to which it flows into in the east, the Gulf of Teneucia similarly serves as both a barrier between two very different regions - the north historically dominated by tribal societies and the south by city-states - and as a conduit for travel, with merchant vessels plying its waves.
In the modern day, the northern coastline of the Gulf of Teneucia is largely under the control of the king and chiefs of Magnia, the west under the city-states of the Machaian League, and the south under the Halakran League. The nation of Kyamita sits on its southern shores, near its narrow-most point before opening into the Sea of Ersas, while Iaramnaean warships just to the east occasionally hassle those traveling between the two bodies of water.