River Tay

River Tay
Tatha
Looking upstream (north) along the Tay from the centre of Perth. In view are St Matthew's Church and Perth Bridge
Location
countryScotland
StateUnited Kingdom
Physical characteristics
SourceAllt Coire Laoigh
  locationBen Lui, Stirling council area / Argyll and Bute, Scotland
  coordinates56°23′07″N 4°47′36″W / 56.38528°N 4.79333°W / 56.38528; -4.79333
  elevation720 m (2,360 ft)
MouthFirth of Tay, North Sea
  location
Between Perth, Scotland and Dundee, Scotland
  coordinates
56°21′18″N 3°17′54″W / 56.35500°N 3.29833°W / 56.35500; -3.29833
  elevation
0 m (0 ft)
Length193 km (120 mi)
Basin size4,970 km2 (1,920 sq mi)
Discharge 
  average220 m3/s (7,800 cu ft/s)
Basin features
Tributaries 
  leftRiver Lyon, River Tummel, River Isla
  rightRiver Almond, River Earn, River Braan

The River Tay (Scottish Gaelic: Tatha, IPA: [ˈt̪ʰa.ə]; probably from the conjectured Brythonic Tausa, possibly meaning 'silent one' or 'strong one' or, simply, 'flowing') is the longest river in Scotland and the seventh-longest in Great Britain. The Tay originates in western Scotland on the slopes of Ben Lui (Scottish Gaelic: Beinn Laoigh), 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 United Kingdom by measured discharge. Its catchment is approximately 2,000 square miles (5,200 square kilometres), the Tweed's is 1,500 sq mi (3,900 km2) and the Spey's is 1,097 sq mi (2,840 km2).

The river has given its name to Perth's Tay Street, which runs along its western banks for 830 yards (760 metres).