It was not a question of whether there should be a hill running round in the Pentland Hills – such an idea has been mulled over by a number of runners over the years. But what hills?

Without obvious height classifications like ‘Munro’, Corbett’ or even ‘Donald’ in the Pentlands, you have to work harder to find a bar that enables you to decide what is in and what is out. A round of the summits over 500 metres is logical, but that would only take you as far north as Black Hill and as far south as Byrehope Mount, inevitably missing out large tracts of the range.

In planning a round (and the hills within that round), I kept the criteria simple: literal prominence and figurative prominence. For the former, the obscure hill-baggers’ list of so-called ‘Tumps’ – summits that have a prominence of at least 30 metres – is a good starting point. There are 39 in the Pentlands, but some can justifiably be discarded. You have to really know these hills to have heard of Easthills and Broomie Law (both close to Dunsyre), or Lead Law and Cock Rig (on opposite sides of the Roman Road between Carlops and West Linton). Black Mount and its lower neighbour, White Hill, were also excluded as they are southern outliers of the Pentlands.

Numbers hold little interest for me. I was far more intrigued by figurative prominence. I call this the Wainwright test. What is the reputation of the hill? What is its aesthetic appeal? Does it add something to a round? By this test, I included White Craig (by Darlees Rig), Dunsyre Hill, Carlops Hill, Grain Heads, Cap Law, Braid Law and Fala Knowe. Some hills that have literal prominence tested this judgement, not least Mealowther and Henshaw Hill, which force a committing diversion off the main ridge. But, again, these hills have tremendous aesthetic appeal, with views east that put the south-western edge of the Pentlands into context. The same is true for Fala Knowe: despite a fairly paltry re-ascent, it rises at the heart of the ring of northern hills. Similarly, stand on Cap Law, looking north to the Kips and South Black Hill, and you will not doubt its inclusion.

After a great deal of indecision, the prospect of actually running the round inspired decision. And so this was my list of hills, including an entirely arbitrary start and finish.

Edwin Muir bench, Swanston

1 Allermuir

2 Capelaw

3 Harbour Hill

4 Bell’s Hill

5 Black Hill

6 Hare Hill

7 Cock Rig

8 Wether Law

East Cairn Hill – East Top

9 East Cairn Hill

East Cairn Hill – West Top

10 West Cairn Hill

11 Muckle Knock

12 Byrehope Mount

13 King’s Seat

14 Catstone

15 Fadden

16 Craigengar

17 Mealowther

18 Henshaw Hill

19 White Craig

20 Darlees Rig

21 Bleak Law

22 Mid Hill

23 Dunsyre Hill

24 Mendick Hill

25 Mount Maw

26 Carlops Hill

27 Grain Heads

28 The Mount

29 Patie’s Hill

30 Spittal Hill

31 Green Law

32 Cap Law

33 Braid Law

34 West Kip

35 East Kip

36 South Black Hill

37 Scald Law

38 Carnethy Hill

39 Turnhouse Hill

40 Castlelaw

41 Fala Knowe

42 Caerketton

Edwin Muir bench, Swanston

I know this selection could be debated for a long time. Why not North Muir Hill (a Tump)? (I was not deliberately excluding anything under 400 metres.) Why Henshaw Hill but not Harrows Law? Why not Faw Mount or Fairliehope Hill or Torweaving Hill or Seat Hill or Woodhouselee Hill? How obscure do you want to go? How pernickety do you want to be? Black Law, the site of the Covenanter’s Grave, niggled me most. I left it out – it is really a spur of White Craig that should be a place of reflection, not a racetrack. I could go on. Every round has a degree of arbitrariness and a round of the Pentlands could be no different.

My round started shortly before dawn on Thursday, July 2, with careful, steady steps up Allermuir, hill one of 42. After seeing two sleepers in bivvy bags on Capelaw, I would not see another person until Ferniehaugh, some seven hours later.

Reversing the so-called Pentland Skyline, I Ieft the route at Red Gate and proceeded over Kitchen Moss. From here, apart from brief respites on the tracks of the Cairn hills and Thieves Road, the route was pathless, wet, tussock-ridden and heathery. (The notable paths in the south Pentlands cross the hills from east to west, further handicapping the runner looking to travel north or south).

The scarcity of paths and the awkwardness of the ground exhausts the mind. Concentration, concentration, concentration. My luck had to run out: I twisted an ankle in the pass between Craigengar and Mealowther. I contemplated limping out to the A70, but I knew I had already come too far to stop. Walking across Bawdy Moss, I grimly committed to the tried-and-tested I-am-here-now-so-I-might-as-well-do-it strategy of round-running. It was rough for two hours or so thereafter – rough and a little disappointing. The longer I spend in the Pentlands, the more I love these hills – and the more I hate them. The spectre of grouse shooting is everywhere: the bones of burnt heather, huts, gravel roads, gun cartridges, crudely-built butts. At times, the ground itself seemed poisoned. My dream for the Pentlands is to be able to stop at a burn and scoop water into my mouth, confident in the knowledge that I am not drinking liquid that has also passed through the decomposing remnants of a sheep.

I reached Dunsyre Hill and cheered up. To stand on Allermuir and Dunsyre Hill, the northern and southern limits of the Pentlands, on the same day, having linked the two, is a little like the Ben Nevis-Beinn na Lap effect on Ramsay’s Round. It seems extraordinary that one could travel so far in such a time, powered only by their legs.

The rest was easier. I had deliberately gone west on a winding route first, enabling a relatively straight-line run home, first over Mendick Hill, then the ridges of Mount Maw, Spittal Hill and Scald Law, where mercifully there are paths that grow ever wider, before the final trio north of Flotterstone. I was tired and nauseous, of course, but a 51-mile run that ascends and descends some 4,000 metres is not meant to be easy.

The time taken – 12 hours, 32 minutes – feels irrelevant. (I say it because, of course, people are interested.) This is my fifth ‘round’ on a round-running CV that includes the Bob Graham, Ramsay’s, Ring of Fire and Rigby. The Round of the Pentland Hills does not compare – but the hills themselves cannot be blamed for that. Should it have been longer? Should I have sought to make my effort closer to 24 hours? I do not think so, for that would see the runner ticking every marginal bump in sight, cursing the heather and their thirst – and what is the sense in going to a place merely for the sake of it? The Pentlands cannot be held up to the awe or historical associations or reverence of the Mamores or the Scafell massif or the Range of the Awful Hand, but these are Edinburgh’s hills, our hills, and we love them dearly nonetheless.