The Tay drains much of the lower region of the Highlands.
It originates on the slopes of Ben Lui (Beinn Laoigh), only around 25 miles (40 km) from the west coast town of Oban, in Argyll and Bute.
In 2011, the Tay Western Catchments Partnership determined as its source (as based on its 'most dominant and longest' tributary) a small lochan on Allt Coire Laoigh south of the summit.
The river has a variety of names in its upper catchment: for the first few miles it is known as the River Connonish; then the River Fillan; the name then changes to the River Dochart until it flows into Loch Tay at Killin.

The River Tay emerges from Loch Tay at Kenmore, and flows from there to Perth which, in historical times, was its lowest bridging point.
Below Perth the river becomes tidal and enters the Firth of Tay.
The largest city on the river, Dundee, lies on the north bank of the Firth.
On reaching the North Sea, the River Tay has flowed 120 miles (190 km) from west to east across central Scotland.

The Tay is unusual amongst Scottish rivers in having several major tributaries, notably the Earn, the Isla, the River Tummel, the Almond and the Lyon.

A flow of 2,269 m³/s (80,100 cu ft/s) was recorded on 17 January 1993, when the river rose 6.48 m (21 ft 3 in) above its usual level at Perth, and caused extensive flooding in the city.
Were it not for the hydro-electric schemes upstream which impounded runoff, the peak would have been considerably higher.
The highest flood recorded at Perth occurred in 1814, when the river rose 7 m (23 ft) above its usual level, partly caused by a blockage of ice under Smeaton's Bridge.
Other severe flood events occurred in 1210 and 1648 when bridges over the Tay at Perth were destroyed.
During the winters of 2009–10 and 2010–11, the Tay froze over as far as the Tay Road Bridge, and ice floes remained for weeks despite a thaw.

Several places along the Tay take their names from it, or are believed to have done so:
Broughty - Bruach Tatha, Bank of the Tay
Taymouth - Near the mouth of Loch Tay.

Tayside - A former Scottish Government region
The Tay drains much of the lower region of the Highlands. It originates on the slopes of Ben Lui (Beinn Laoigh), only around 25 miles (40 km) from the west coast town of Oban, in Argyll and Bute. In 2011, the Tay Western Catchments Partnership determined as its source (as based on its 'most dominant and longest' tributary) a small lochan on Allt Coire Laoigh south of the summit. The river has a variety of names in its upper catchment: for the first few miles it is known as the River Connonish; then the River Fillan; the name then changes to the River Dochart until it flows into Loch Tay at Killin.
The River Tay emerges from Loch Tay at Kenmore, and flows from there to Perth which, in historical times, was its lowest bridging point. Below Perth the river becomes tidal and enters the Firth of Tay. The largest city on the river, Dundee, lies on the north bank of the Firth. On reaching the North Sea, the River Tay has flowed 120 miles (190 km) from west to east across central Scotland.
The Tay is unusual amongst Scottish rivers in having several major tributaries, notably the Earn, the Isla, the River Tummel, the Almond and the Lyon.
A flow of 2,269 m³/s (80,100 cu ft/s) was recorded on 17 January 1993, when the river rose 6.48 m (21 ft 3 in) above its usual level at Perth, and caused extensive flooding in the city. Were it not for the hydro-electric schemes upstream which impounded runoff, the peak would have been considerably higher. The highest flood recorded at Perth occurred in 1814, when the river rose 7 m (23 ft) above its usual level, partly caused by a blockage of ice under Smeaton's Bridge. Other severe flood events occurred in 1210 and 1648 when bridges over the Tay at Perth were destroyed. During the winters of 2009–10 and 2010–11, the Tay froze over as far as the Tay Road Bridge, and ice floes remained for weeks despite a thaw.
Several places along the Tay take their names from it, or are believed to have done so:
Broughty - Bruach Tatha, Bank of the Tay
Taymouth - Near the mouth of Loch Tay.
Tayside - A former Scottish Government region
River Tay