Back and Forth
There’s little point in denying that this post will appeal to only the most dedicated of geography geeks. It is a longish and, frankly, sometimes dull voyage into the extremely niche study-area of river sources. Along with seeking out patches of snow, it is another hobby of mine that defies any form of logic. It also partly explains why I am useless at popular culture quizzes and anything that involves a knowledge of film or TV post-1996. Anyway, for the river aficionado there is a sufficient amount of trivia in here to keep you occupied for an absolute minimum (and maximum) of five minutes.
Trying to find the source of a river is notoriously difficult. Not only is there no defined and accepted terminology on what ‘source’ means, tributaries of rivers are often longer and more distant from the sea than the main river which takes the name. Therefore, when embarking on a trip to find the point of a river’s system that truly deserves the epithet source you really need to be prepared to disregard what the internet, and to a certain extent fact, tells you.
A few years ago I went to the remote high ground in the Lowther Hills to try and find the ultimate source of the River Clyde. I’m fairly sure that day I managed to locate the point in the river’s catchment which was farthest from the sea, so it was a good outcome. With that day in mind, then, I embarked on a similar trip recently to the wilds of the Southern Highlands to see if I could track down the point in the River Forth catchment that was as far from the sea as possible. Along with the Clyde, the Forth is the Central Belt of Scotland’s most famous river, so it seemed like a good way to kill another lock-down day.
The first conundrum, however, was where to even begin looking for it.
The Forth is known across the UK — and to a lesser extent the world — for its exceptional Victorian railway bridge, and for the fact that Scotland’s capital, Edinburgh, sits at the mouth of the river as it develops into an estuary (or a ‘firth’). But, actually, does the river that passes into the North Sea merit having the name ‘Forth’? That’s as much a rhetorical question as anything, but it does have significance here.
The Forth catchment area is a very modest size, at just 1036 km2. This is quite small even by Scottish standards (the Tay’s is 4991 km2). However, the high hills that feed the headwaters of the river are some of the wettest in the country, meaning that despite its diminutive catchment size the river churns out an impressive average of 46,000 litres of fresh water every second at Stirling. (A litre is the same as a kg, so that’s 46 tonnes per second. ) This is comparable with the Dee and the Clyde. In terms of volume it punches well above its weight.
Most of that water at Stirling, though, doesn’t come from the Forth itself, but — rather — its main tributary, the Teith. And this is what led to the conundrum I mentioned above. The Forth and the Teith meet at Stirling, but the former keeps the name despite it being far smaller in terms of volume and catchment size. Why this should be I’ve no idea. Doubtless there is a historical reason for this, but I have not been able to work it out.
Anyway, this gave me a problem. Where, then, in the absence of an authoritative definition ought I to go to find the river’s genesis? Do I retrace the Forth itself or do I strike for the uppermost reaches of the Teith? In the end I opted for the latter on account of its longer length and distance from the sea. For me these criteria have always seemed more persuasive when working out a river’s ultimate root.
You’d think, therefore, that having arrived at the decision to retrace the Teith that it would simply be a case of working back up its course on a map and finding its source. Ah, if only it were that easy. Alas the river takes the name for a brief 12 miles back upstream from Stirling to Callander, whereupon it splits. Rather unhelpfully, neither of the two rivers that conjoin to make the main river carry the name Teith, so one is forced to then make another decision about which branch to follow.
Looking at a map, it is obvious that the Eas Gobhain (the smith’s waterfall or rapid), which flows west to east, is slightly shorter than the Garbh Uisge (the rough water). The latter strikes north for some miles before turning west. The former has no such kink, and it is therefore deprived of many miles length as a result.
Also, according to the two measuring stations that are positioned just before the confluence (here and here) the Garbh Uisge is significantly larger, totallying 13,000 litres per second discharge against the Eas Gobhain’s 7,700 litres. For these reasons, then, I decided that the Garbh Uisge would be the natural river to retrace.
It was a fine morning on the 24th April when I set out from the head of the unclassified road at Inverlochlarig, an isolated farm about 10 miles from the A84. This part of the Southern Highlands, though reasonably close to main roads, has a real wild quality to it. The glen is a cul-de-sac, so no passing traffic ventures there. And although it has access points to many Munros in the area, most people tackle these from the north.
I walked east-to-west (right-to-left) on the track which clung to the River Larig (another of the many names the river has during its journey to the sea), heading for the point at which it struck upwards and onto the shoulder of Beinn Chabhair. I always enjoy this type of walking. There are no paths, save for faint deer tracks, and even fewer people. The upwards pull, though steep, was lovely on soft, dry and springy turf. A few scrambly sections kept the interest going as the stream became smaller and smaller as altitude was gained. It really was just a case of following the water course upwards, negotiating a few rocky sections along the way.
Finally, though, near the summit of Beinn Chabhair the ground flattened off and I came to a natural bowl. The stream, by now little more than a trickle, disappeared into a boggy section and disappeared. On the other side of the bog a small spring bubbled out from the ground. It was at this point, almost 3,000 ft up and as far from the sea as it is possible to be in the Forth catchment, that I concluded that this was the source of the river that carves its way through — physically and metaphorically — central Scotland.
River sources and wells have, and have always had, a special significance. Votive offerings were often given at wells, especially in Roman times. Due to the remoteness of this spring, though, I doubt many have ever made the pilgrimage here to cast bronze coins into the water, and I suspect few others will in the future. It will stay a little-visited and little-cared-for place, but all the more special because of that.
