some personal notes in conclusion
There is much variation but it is typically accepted that the Bob Graham Round is around 65 miles long with 27,000 feet (8,330 metres) of ascent. Readers will be pleased the author can corroborate those figures. Note that this number does not take account of the difference between horizontal distance and actual distance travelled. As noted in the introduction, this analysis estimates the latter (which will be greater than the former, especially given the nature of the BGR which involves a significant degree of ascent and descent over a relatively short distance).
If one could travel direct between summits, across any form of terrain, the shortest BGR possible is 56.1 miles. That would entail 9,300 metres (30,600 feet) of ascent. Some of this involves heading through buildings, trespassing and walking on water. If we take account of public rights of way and stick to legal, dry ground then the summary numbers are 58.0 miles and 9,400 metres (30,800 feet) of ascent.
So route finding is adding nearly 10 miles of distance and saving around 4,000 feet of ascent. This feels reasonable: as we know, many of the route choices involve a trade-off between distance and ascent. This tells us that corners can be cut, but probably not much.
If one looks at all the “legitimate” route variations, what is the shortest advisable BGR? The calculation is 64.5 miles (104 kilometres) with 8,100 metres (26,500 feet of ascent). For reference, the 42 peaks pamphlet states that “through careful study the map”, Billy Bland managed to get the BGR distance down to 65 miles for his walking round. Allowing for measurement differences this number feels in the right ball park (and makes sense given the cutting of corners would be entirely feasible and highly likely for a fellsman of Bland’s quality).
What is the longest BGR that a sane contender might attempt? Totting up the options to maximise distance (an odd objective, admittedly) gives 69.6 miles (112 kilometres), with 8,080 metres (26,500 feet) of ascent. So 5 miles difference but little difference in gross ascent once all is aggregated.
What if you hate the climbs? Go do the marathon. Alternatively, the minimum gross ascent that the options can deliver is 7,810 metres (25,600 feet). So you've saved the equivalent of an ascent of Latrigg. The associated distance is between 66.3 and 67.2 miles depending on the route taken.
Returning to the theoretical, ignoring paths and lines, the minimum possible gross ascent for the whole round is 7,490 metres (24,600 feet). So you can win back another 300 metres of ascent if terrain is ignored – another ascent of Latrigg. All in all, there is more variation in distance than ascent.
All that said, the only sensible conclusion to draw is there is nothing about the Bob Graham that can be reduced to bare numbers save for 24 and 42. Lines on maps feel very different on the ground and aspiring fell analysts should remember no contender has yet completed the round from their armchair.
With that in mind, these descriptions are but a humble tribute to the diversity of the Bob Graham Round and its Lake District home.
For each transition, a table provides simple statistics. It summarises the distance and gross ascent of each route option.