Girdle of Melian

The Girdle of Melian was an enchanted barrier surrounding the realm of Doriath throughout much of its existence.
It enclosed the three forests of Neldoreth, Region, Nivrim and part of the land of Aelin-uial.
All those who attempted to pass through it became enmeshed and wandered aimlessly as if lost in an impossible maze of trees, placing them in a situation where their food would eventually run out and they would die.
The Girdle also protected Doriath from the dark influence and prying eyes of Morgoth.

Girdle of Melian

Realm of Ossiriand Irena