Forest of Brethil.
Brethil was covered by the Forest of Brethil. In the South of the Narrow Land was the North-Western-fringe of Forest of Brethil running 30 Miles East to the Ford of Brithiach and Dimbar where it turned South South-East following the Westshore of Sirion and Dimbar 50 Miles to the junktion Sirion / Mindeb.
Sirion continued between Forest of Neldoreth and Brethil for 15 Miles until Teiglin, a tributary to Sirion and Southern border of Brethil, came from the West. From the North-Western corner ran the Ancient Road 30 Miles South to the Crossing of Teiglin where the eaves of the forest followed Teiglin 80 Miles East South-East to Sirion. At the widest was Brethil 70 Miles East / West and 50 North / South. A total area of about 50 squaremiles.
Brethil belonged to the realm of Doriath but was not guarded by the Girdle of Melian and when the Secondborn came over the Ered Luin Thingol granted the people of Haleth the land if they would aid in defending its borders and the intrances to Beleriand and his realm. This they did with honour and courage and friendship grew among the two people. The people of Brethil raised there home; Ephel Brandir and Obel Halad upon the hill Amon Obel in the midst of the forest. At the Western side of the forest was the Haudh-en-Elleth. A single river came from the forest and ran to Teiglin, this was Celebros who had its spring in the North-West of the wood but before it came to Teiglin it had a fall called Dimrost.