As thus determined, it runs southeast from Loch Resort up Clàr Beag to Loch Chleistir, then east along Bealach na h-Uamha to the River Langdale, then northeast through the peaks of Tom Ruisg, Mullach a' Ruisg, and Mullach Bhìogadail, east to Amhuinn a Mhuil, and downstream to where it enters Loch Seaforth at Ath Linne under the A859, the only road connecting Lewis and Harris.