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
Tay Rail Bridge likely to be encountered during the entirety of its service life. According to the reports submitted, the results from this testing were satisfying, clearing the way for operational use. On 11 June 1887, the first passenger-carrying trains passed along the second Tay Bridge. On 20 June 1887, which also happened to be the fiftieth anniversary of Queen Victoria's accession, the bridge was opened for use by general traffic. The second Tay Bridge has remained in use to the present day. To protect the structure from sustaining damage, the double-heading of locomotives is prohibited on all trains that traverse the bridge;