Scottish watershed

The Scottish watershed is the drainage divide in Scotland that separates river systems that flow to the east into the North Sea from those that flow to the west and north into the Atlantic Ocean. At a point on the summit of Ben Lomond for example, looking west all water flows to the Firth of Clyde, and looking east all water flows into the Firth of Forth. Similarly Cumbernauld is a point on this line and arguably its Gaelic name has, for hundreds of years, reflected this fact. There is some dispute however about interpretation of the Gaelic phrase. The line joining all such points in Scotland is the Scottish watershed.

Although the concept of geographical watersheds is common, the first unequivocal reference to the Scottish watershed is to be found in Groome's Ordnance Gazetteer of 1884, in which the entry defines the northern terminus as being at Duncansby Head. This was followed in 1912 with the Bartholomew Atlas Survey (NLS) which shows the entire geographic feature, from the border with England to Duncansby Head. The first popular delineation of the Scottish watershed took place as recently as 1986. It was mapped out in that year by Dave Hewitt, who in 1987 then walked the line of the watershed from south to north. The Royal Scottish Geographical Society (RSGS) reviewed Wright`s `Ribbon of Wildness` in 2011, and in acknowledging the significance of the route, stated that "Ribbon of Wildness gives a vivid introduction to this hitherto largely unknown geographic feature". Eight people have now done versions of this route:

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