The Oykel rises on the slopes of Ben More Assynt, Sutherland's county top, a few miles from Ullapool on the west coast. The Oykel though drains to the east. At Rosehall, Sutherland, still 12 miles from the head of Dornoch Firth, the river becomes tidal and this long tidal reach is known as the Kyle of Sutherland.
The river rises at a height of 1,500 feet on the southern side of Ben More Assynt, and flows just over 35 miles. The upper valley is known as Glen Oykel and is mostly desolate moorland. The lower valley is known as Strath Oykel. The A837 road runs along the river for most of its length, crossing it just above the junction with the Einig, about six miles west of Rosehall at Oykel Bridge. The Oykel Bridge Hotel is famous among anglers, who are obliged to stay there when fishing the river.
The Kyle of Sutherland may be deemed to begin near Rosehall where the river becomes tidal, though for many miles it has the appearance of a broad river. The River Cassley feeds into this waterway by Invercassley, and it is which is later joined by the River Shin and at its mouth by the River Carron. The Kyle discharges into the North Sea by way of the Dornoch Firth.
The Oykel was known to the Vikings as the Ekkjal. It served as the boundary between the ancient Pictish province of Cat (Sutherland and Caithness), and the province of Ross, a role it has maintained.
In 1406, the Mackays defeated the Clan MacLeod of Lewis at the Battle of Tuiteam Tarbhach on the north bank near the mouth of the Tutim Burn.
Flora and fauna
It is designated as a Special Area of Conservation. It has abundant stocks of salmon and over 1000 were caught by anglers in 2007.
- Location map: 57°58’4"N, 4°43’56"W
- River Oykel at the Gazetteer for Scotland site
- Special Area of Conservation data at the Joint Nature Conservation Committee site
- Anon (1764). The History of the Feuds and Conflicts Among the Clans in the Northern Parts of Scotland and in the Western Isles: from the year M.XX1 unto M.B.C.XIX, now first published from a manuscript wrote in the reign of King James VI. Foulis Press. http://www.electricscotland.com/webclans/conflict/Tuiteam_Tarbhach.html.
- "River Oykel Noticeboard". Kyle of Sutherland District Salmon Fisheries Board. 2008. http://www.dsfb.co.uk/river-oykel-noticeboard.shtml.