Scientists from the conservation group, Scottish Native Woods, have at long last discovered the source of one of Scotland’s major rivers – the Tay. It is the only one of Scotland’s great salmon rivers not to have had a single definitive source.

The scientists had to track more than 1,000 miles of waterway on foot but they hunted their quarry down – 500ft further west than thought before – up in the hills above Tyndrum in north Argyll.

Consequently, expert opinion is now that the definitive source of the Tay rises only 20 miles from the west coast port of Oban. It is the little burn, Allt Coire Laoigh, emerging between Ben Lui and Ben Oss and falling into the River Cononish. The Cononish feeds into the Fillan which then feeds the Dochart which itself flows into the western end of Loch Tay. And the River Tay flows out of the eastern end of the loch at Kenmore near Aberfeldy.

Scottish Native Woods’ Victor Clements, who is its Highland Perthshire Manager, says: ‘The Tay river system is massive, with the biggest catchment area in Britain. From mid-summer this year, during our rsearch, it had been our intention to to finish at the very source of the Tay on Ben Lui. However, on reaching the upper Cononish it became obvious that this was not at all straightforward’.

From 1780 onwards Ben Lui has been regarded as the source of the Tay but with no single water identified. A book written by Joan Pearson in 1975, Tales of the Tay, named the burn, Allt na Rund. As the furthest westerly burn and the longest tributary it was assumed to be the source of the mighty Tay.

However, the expert explorers found that the Allt Coire Laoigh is 500ft longer than the Allt na Rund and is more substantial. Mr Clements says: ‘Logically this shoud be the source. For the record, we think that, as it is the most dominant tributary and the longest, the answer to the mystery is the Allt Coire Laoigh’.

You can see the source of the Tay and a lot of Ben Lui – with some sense of the conditions these experts were working in – on their blog on the Scottish Native Woods website linked above. This blog will also give you a lot of additional fun watching short videos of otters, red squirrels, a canoe crunching through ice on the River Dochart – and other delights.