Loch Shiel (Scottish Gaelic: Loch Seile) is a 17+1/2 mi freshwater loch, 120 m (393 ft) deep, situated 12.4 miles west of Fort William in Lochaber, Highland, Scotland, at the south west it ends  the 4 km River Shiel drains to the sea in Loch Moidart near Castle Tioram, Castle Tioram ( ) (Scottish Gaelic: "Caisteal Tioram" , meaning "dry castle") is a ruined castle that sits on which tidal island in Loch Moidart, Lochaber, Highland, Scotland?
Loch Shiel:  Its nature changes considerably along its length, being deep and enclosed by mountains in the north east and shallow surrounded by bog and rough pasture in the south west, from which end the 4 km River Shiel drains to the sea in Loch Moidart near Castle Tioram.
i don't know