Niwray Border was a border region between the Clans Lornak and Tralesta in the late 23rd century. Following the Maurody Storms of 2286, the disputes along this border escalated into a series of brutal reprisals which spilled over into the Jimbern Regions and, eventually, culminated in the Tralesta Massacre.
In 2366, this border region was mentioned in the history file of the Tralesta Massacre, which were accessible to the crew of the USS Enterprise-D via the Acamarian planetary database. (TNG: "The Vengeance Factor", okudagram)
This region was only mentioned in writing.