River Tay River Tay The River Tay () is the longest river in Scotland and the seventh-longest in the United Kingdom. The Tay originates in western Scotland on the slopes of Ben Lui (), then flows easterly across the Highlands, through Loch Dochart, Loch Iubhair and Loch Tay, then continues east through Strathtay (see Strath), in the centre of Scotland, then southeasterly through Perth, where it becomes tidal, to its mouth at the Firth of Tay, south of Dundee. It is the largest river in the UK by measured discharge. Its catchment is approximately , the Tweed's is and the Spey's is
Loch Tay Loch Tay Loch Tay (Scottish Gaelic, "Loch Tatha") is a freshwater loch in the central highlands of Scotland, in the Perth and Kinross and Stirling council areas. The watershed of Loch Tay traditionally formed the historic province of Breadalbane. It is a long, narrow loch of around long, and typically around wide, following the line of the strath from the south west to north east. It is the sixth-largest loch in Scotland by area and over deep at its deepest. Ben Lawers on its north shore is, at , the tenth-highest mountain in the British Isles, and is the highest