I was looking at some Spine Race statistics the other way and was quite surprised to see that over its length it accummulates some 37,000ft of ascent. Now the Pennine Way is in many respects quite a challenging trail regardless of the weather conditions (lots of wet ground, path indistinct in places, often a long way between contacts with civilisation, etc) but I think you'd have to stretch a point quite a distance to describe it as hilly. But it's a long way, so if you imagine some sort of measure of ascent per mile it probably wouldn't score very highly. This thought got me interested, so I worked out a "rate of climb" for a number of events that I have an interest in, to see how they compare.
To get the rate of climb, I have divided the total ascent by half the distance of the race (on the basis that most races have a similar amount of ascent and descent), expressed as a percentage. So if the race has a 5% rate of climb, you will on average be going up a 1 in 20 hill for half the distance, and down a 1 in 20 for the other half. The races I've chosen are a purely personal selection, comprising many that I've done or attempted, and some I might have a go at one day.
Now as I've said before, how difficult an event is to finish depends on a lot more than just its length and steepness - ground underfoot, difficulty of navigation, likely weather conditions and particularly the time constraints imposed by the organiser all play a part. But if you want to compare the simple physical characteristics of the undertaking, then I think the table below can give some pointers.
Race Length (miles) Total Climb (ft) Rate of climb (%)
The Spine 268 37000 5
Tor des Geants 206 78700 14
PTL 187 91800 19
Dragon's Back 182 51400 11
Ring of Fire 135 12000 3
Hardmoors 110 110 16700 6
UTMB 105 31500 11
Lakeland 100 105 22500 8
Spine Challenger 105 16400 6
West Highland Way 95 13300 5
TDS 74 23800 12
UT Lakes 110k 69 10800 6
Bob Graham Round 66 27000 15
CCC 63 20000 12
Hardmoors 60 62 10300 6
10 Peaks Brecons 56 15700 11
Hardmoors 55 53 6400 5
Highland Fling 53 5900 4
Lakes in a Day 50 13000 10
Lakes 3x3000 50 13000 10
Lakeland 50 50 9700 7
10 Peaks Lakes 46 16400 13
Grand Tour of Skiddaw 44 7700 7
White Rose Ultra (30) 30 4700 6
I'm sure there will be one or two distances or heights that people may not agree with, but I've tried to get the figures from the best available sources (since last year the UTMB list has required a GPS trace, so I'm assuming these are pretty good for those events represented there - it's clear that before that a number of races claimed rather inflated figures for total ascent), but anyway they are accurate enough for some sort of comparison.
What's interesting is that with some knowledge of how the races above actually pan out on the ground, you can see that there are some clear break points where the game changes for the average runner. Events with up to around a 5% rate of climb are runnable pretty well all the way (if you're fit enough for the distance of course!) Events like the Highland Fling, the West Highland Way and the Ring of Fire are running races. Forget about The Spine because of the conditions - the Pennine Way in summer with a light rucksack is runnable ground.
Once you get into the 5-10% range you're into the races where most people will walk a lot of the uphills, but there will be quite a lot of runnable ground in between. This covers the Lakeland 50/100 events and the Harder bits of the Hardmoors.
Above 10% and you're into seriously steep territory - most will walk all the ups and shamble the downhills, and only the talented will average better than 3 miles an hour.
And just out of interest, the Barclay Marathons? To add to the tree roots, briars and mudslides, a mere 21% rate of climb.