At 119 miles long, what is the name of Scotland's longest river

What is the name of Scotland's longest river - 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, 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.

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