North Downs Way 50
Posted by Ed on May 23, 2025
The North Downs Way 50 is a 50-mile ultramarathon from Farnham to Knockholt via the North Downs Way National Trail, hosted by Centurion Running. I finished in 7:53 as the 8th male and 9th overall.
I first ran NDW50 in 2021, as part of Centurion’s Grand Slam of four fifty milers in a calendar year. I finished in 9:32. Since then, I’ve returned to Wendover Woods (2022) and South Downs Way (2023), but NDW and Chiltern Wonderland had so far not tempted me back. Indeed, I probably would have ranked NDW as my least favourite of the four at the time. As I hope this race report will make clear, that perspective has since shifted.
The defining feature of NDW50 as a race is the contrast between the first and second halves of the course. The first 25 miles, whilst not exactly pancake flat, are very runnable – a mix of wide country lanes, riverside paths, and forest trails. There are only really two substantial climbs – St Martha’s Hill and a nameless ascent up onto the ridgeline proper of the North Downs – and each is over in a few minutes. The rest is flowy, rolling terrain – a road runner’s trail run, if ever there was one.
From Box Hill onwards, however, the course undergoes a personality shift. The climbs become more substantial (Box Hill is just the first of four or five major climbs in the second half), the ground underfoot grows more technical, and the trail gets much more varied, changing in character every few miles as it weaves through fields, forests, country lanes and suburban edgelands. It’s much slower going than the first half and plays more to the strengths of out-and-out trail runners.
This contrast was, I think, the reason I ranked NDW50 as my least favourite Centurion 50-miler back in 2021. As a newbie ultrarunner who had only set foot on part of the course, I found its constant twists and turns disorienting. It was like arguing with someone who keeps changing their mind mid-discussion – I felt like I was always on the backfoot, caught short.
Returning four years later, though, and I have developed a newfound appreciation for the route. It rewards so much of what I love about ultrarunning as a sport, skills I like to think of as my relative strengths: patience, strategy, race management, and an aptitude for ascending. I suspect it’s a race to which I’ll return in future, as, happy as I am with my performance this year, I can already see where it would be possible to make up time. But more on that later.
Pre-Race
I didn’t sign up to NDW50 this year until three weeks before the race, the day of the deadline to enter. I was supposed to be running the Chiltern Hills 100k in April, hosted by Runaway Racing. I’ve enjoyed attending and supporting Runaway’s events for almost five years now, and wanted to be there for their inaugural 100k, which I had hopes of podiuming.
Unfortunately, the week of the race, a mild taper flu turned into a bad migraine, which left me bed-bound most of Friday. With less than 12 hours to go before the start, I decided to DNS – I could possibly have hobbled around to a finish, but I knew it wasn’t going to be possible to get the best performance out of myself. Gutted, but also a bit relieved at having taken the pressure off for that weekend, I signed up for NDW50 a few hours before the deadline.
Having already undergone a three-week taper, I wasn’t sure how best to navigate the subsequent three weeks before the race. I opted to run a single higher volume week, hitting around 90km/1100m with a couple of workouts in there too. (I managed a 5km PB (16:40) at an Assembly League race that week, which I chalk down to having effectively tapered for three weeks beforehand!) The focus was on reintroducing a bit of tension back into my legs and squeezing out a few extra drops of fitness gains before diving back into another (two-week) taper.
For my long run that week, I headed out to Merstham and ran the final 27km of the course to Knockholt Pound. I was really glad to have done this come race day, as there are a couple of climbs in that final stretch that pack a punch if you’re not ready for them.
Also, having raced the North Downs Ridge 50k back in February and having run from Box Hill to Merstham countless times in training, the only section I was now not familiar with was the initial bit from Farnham to Guildford, which I knew to be flat and early enough in the race not to worry about.
Ahead of the race, I reviewed my splits from four years ago and did a back-of-the-envelope calculation to figure out what might be possible. I’d run 7:58 a South Downs Way 50 in 2023, a massive improvement on my 2021 time of 9:12, so I knew that I could expect to take a similarly substantial bite out of my 2021 NDW time of 9:32. The course being a bit long (51 miles is the general wisdom), and SDW being a bit short (49 miles), meant comparing the two is tricky, but I worked out an estimated time of somewhere between 7:30 and 7:50.
The Race
The night before starting I realised I had forgotten a couple of key items of (non-mandatory) kit – a pair of sunglasses and my heart-rate monitor. The former I knew was easily replaceable at the Centurion store at registration, but the latter was a bit frustrating, as I tend to rely upon heart rate to gauge how hard to push in races. (I had planned a general rule of thumb to stay in zone two on the flats and zone three on the climbs.)
I decided to embrace it, though, turning off the wrist-based heart rate monitor on my Suunto and running entirely to feel. This proved massively liberating and I will probably continue to ignore heart rate data in future races, though I’ll probably still track it to review afterwards.
After an expectedly smooth registration and bag drop, the first wave of runners headed over to the roadside bike path where the North Downs Way officially starts. I made my way towards the front of the pack, maybe 20 runners back, just to avoid getting caught in a conga line. Fi Pascall zipped past me just before the race started and took her place at the front, and bang on 7AM the race began.
Almost immediately, I was surprised by how quickly everybody was taking it out. The lead pack disappeared into the distance, as I expected, but despite feeling confident in my projected sub-8 finish and the thin company that would put me in, I was surrounded from the outset by people who were absolutely gunning it. I tried my best to ignore my ego, which urged me to kick ahead, and instead focused on channelling my inner Josh Barrow, running at a nice cruising pace, staying hydrated and well-fed.
On that subject, a brief aside to outline my nutrition plan, which was a major factor in my success at this race. I broke it down into three main components:
- Carbohydrates: Having spoken to multiple athletes on my podcast about the benefits of a high carb approach, I’d been practicing ingesting 90g per hour and had gotten to the point where my stomach could handle it no problem.
- Water: I’d done a couple of home sweat tests and had been surprised to learn that in warm conditions (20+ degrees) I tend to lose 1.3L of liquid per hour – far more than I had ever been taking on in previous races.
- Sodium: I used Precision’s simple subjective questionnaire about how salty your sweat is to guesstimate that I probably had averagely salty sweat, or perhaps slightly less than average. I aimed for 1000mg of sodium per hour to be safe.
All three of these components came together beautifully in the race. For carbohydrates, I relied upon a combination of Precision gels, including a caffeinated gel every couple of hours, and Voom powder – I premixed one flask and had two more loaded with powder in my waistband ready to fill with water at aid stations. For water, I was carrying two 500ml flasks up front plus an additional 300ml flask in the back of my waist belt. I always made sure this smaller flask had a 1000mg Precision electrolyte tab loaded into it which I got through at a rate of roughly one per aid station.
Balancing these inputs can be tricky, especially later in a race, but I found that I was able to stay on top of all three. Particularly early in the race, I hydrated well enough that I had to stop to pee four or five times. Whilst a bit frustrating, I knew it would pay dividends to be topped up when the heat kicked in later in the race.
Having finished off a bottle of Voom before the first aid station, I filled up my second pre-loaded bottle at Puttenham and pressed on. I spent a few miles leapfrogging with my buddies Russ and Harry, both fellow south east Londoners who were taking on their first ultra. Shortly after crossing the Wey at Guildford Harry peeled off to use a public loo and that was the last I saw of either of them.
Before I knew it, we hit a stretch of trail that I recognised, and I realised we had hit the turnaround point on the North Downs Ridge 50k course and I was on familiar territory. From here to the finish, I more or less knew what was around each corner, which was a big psychological boost. I can’t recommend enough recceing as much of the course as you can for your next ultra, it just pays dividends come race day.
By now the early enthusiasts had all fallen behind and the field had thinned out. I could usually only see one or two runners up ahead or behind me at a time. I picked my way up St Martha’s Hill, the first substantial climb of the day, managing to avoid walking for all but a few seconds on the very steepest grade.
Not having my heart rate monitor to give me any hard data about my output was a bit tricky, but I didn’t feel as though I’d lit any matches by running the whole thing. Plus, I knew there was an immediate descent afterwards on which I could catch my breath – this is a super fun stretch of trail, it’s technical yet somehow not at all challenging. Pierre the photographer did well to position himself there, catching runners as they flew and hopped down.
As soon as you hit the bottom of this trail, the course kicks uphill again on a narrow, twisty section of singletrack that brings you out onto the main ridge of the North Downs. Here the terrain changes from loamy sandstone and dirt to the chalk characteristic of the main ridgeline. I caught up with a woman in green shorts who I later learned to be Veronika Gill (eventual 3rd place) and ran with her for a bit before peeling ahead on the wide open field section just before Newlands Corner.
Up ahead I could see Jess Gray, a friend and previous winner of this race who I’d not seen in years. I caught up with her just as we hit the aid station, where more friendly faces awaited – my clubmate Ali and London 100k winner Anna both said hello and offered me words of encouragement. I did my best to be in and out, electing only to refill water this time and keep my third and final pre-loaded Voom bottle back for later in the race in case gels started giving me any issues.
I knew the wide forest tracks and paved roads that take you from Newlands Corner to Box Hill to be fast, and so I picked up the pace a bit heading out of the aid station, perked up from having spotted some familiar faces. With a good quarter of the race behind me, I was feeling really fresh and quite enjoyed the feeling of running at pace, though I was still making sure to leave plenty in the tank for the tougher climbs later on.
Jess and I ran together for a stretch and chatted before I found myself pulling ahead on some of the more technical singletrack. I focused on listening to my body and letting it roll, and was pleased with how sustainable sub-5 minute kilometre pace felt once I hit the road just before Denbies. I could tell the early focus on fuelling and hydrating was already paying off, though I did have some minor stomach grumbles upon transitioning from Voom to gels, particularly on the downhill heading towards the A24. Thankfully this didn’t persist, and before I knew it I’d nipped through the underpass and was at the foot of Box Hill. Time elapsed: 3:20. A full 20 minutes faster than I’d projected and 40 minutes up on 2021.
At the Box Hill aid station, I made sure to fill up all my bottles, knowing the next section could be the longest gap between aid stations in terms of time. The climb up to the summit, as ever, was a slog. It’s just very hard going. And unless you take it super easy you just have to light a few matches to get up it. But I was approaching halfway by this point and happy to push things up a gear in order to feel like I was making good progress.
Upon reaching the top there were tons of people out enjoying the May sunshine cheering runners on, which was really a lovely feeling. The trail in the following miles really marks the shift from the gentler stuff early on, with plenty of twists and turns on a mix of exposed roots and chalky gulleys. It’s all still broadly in the category of ‘runnable’ when you compare it to the full spectrum of what’s possible in trail running, but with 40k in your legs you do have to work quite hard to maintain a sense of flow.
I continued to catch people in this section. One guy put up a bit of a fight when he spotted me over his shoulder, and I was happy to cruise along behind him until we hit the bottom of a particularly rough set of steps, where I pushed ahead up the climb. By the time I got to the school at Reigate any other runners were out of sight, ahead or behind me.
Climbing Reigate hill (worse than Box Hill in my estimation) I did my best to shuffle into a run as much as I could, though I was forced to power hike most of it. The views atop the hill were as epic as I remembered, and I found myself reflecting on the contrast between 2021, where I remembered feeling like death at this point, and now – running strong on the gentle uphill gradient, feeling satiated and comfortable. A glance on my watch told me I’d gone through the 50k mark in 4:30, which in would have been a PB until last year. Progress is gradual but when you take a moment to do the maths it can be remarkable to reflect on how far you’ve come.
At the Reigate Hill aid station I once again decided not to top up my third Voom bottle as gels were going down well. I took advantage of the opportunity to hydrate, downing half a bottle of water and pouring the rest on my head before fully topping up my supplies once more. By now the heat of the day was kicking in, though it never felt too bad on the trail, which is largely covered by foliage. As I readied myself to leave one of the volunteers told me I was in 9th place – I wasn’t sure if he meant overall or in the men’s field, but it was a huge boost to find out that I was in the top ten either way. Though I took it with a pinch of salt as these things are easy to misjudge, and there was still a lot of racing to be done.
After pressing on I soon found myself back on very familiar ground from my recce two weeks earlier as I skirted around Merstham. Heading down Rockshaw Road I started to get paranoid that the long sight lines would expose me to the phantom runner chasing me down, but the opposite proved true – a few hundred metres ahead, I spotted a bib and smelled blood in the water. I didn’t push any harder, though, trusting that I had the time to play with and let myself naturally catch up to him.
Unfortunately, when I did finally catch him, I realised he wasn’t in the race at all – just a random guy out for a run. On the long drag of a climb up through the field with the roar of the M25 behind me, we ran side-by-side, which I was slightly worried about in case someone spotted us and accused me of pre-arranging a pacer. He was breathing substantially more heavily than me, though, and I must admit to feeling rather smug that almost 60k in I was able to run uphill.
As we crested the first false summit of the climb, two things happened: first, I glanced behind, all the way back to the bottom of the hill and saw – nobody. I deduced that I had at least a 3-minute lead on whoever was behind me, which felt comfortable. Second, I looked ahead towards the actual summit, and saw a green race vest dart out of view behind some foliage. Again, I didn’t want to get carried away chasing a ghost – but I knew that catching someone was a possibility.
The runner I’d been cruising next to peeled off and wished me well. The next few miles I knew to be a bit tricky, with a few shallow gradients where it’s important to keep up the pace or else you can haemorrhage time. My legs were getting quite sore but with the bulk of the race behind me I knew I could afford to push things a bit closer to the wire. At the foot of Botley Hill I braced myself and started jogging up it – to my delight, I was able to gently run the whole thing. A couple of spectators sat by the side of the trail near the top gave me some encouragement and told me I was the first person to run the whole thing they’d seen that day.
As I entered the aid station, the green-vested runner I’d seen climbing out of Merstham was leaving. He looked a bit beaten up and was walking on the pavement. I smelt blood in the water. I went to quickly refill my bottles and douse myself in cold water, and in the aid station itself I spotted another runner, who again was looking quite broken. He made no effort to hurry when he saw me, and as I left he was still sorting himself out.
With just 11km to go and a clear target to chase in the form of the runner who’d left just ahead of me, I felt rejuvenated as I left Botley Hill and made my way towards the finish. A couple of miles later, I caught up with him as he was walking up a climb through an open field. I made a point of not pushing to overtake him, but allowing the natural difference in our paces (I was still running) to play itself out. When he glanced back and saw me, he didn’t pick up the pace at all. As I passed we exchanged words of encouragement. But I let myself push a little bit to put a bit of distance between us.
Having passed a runner so near the finish, I had some minor paranoia about him catching me again – I tried to use this to fuel my fire a little bit and keep him out of view behind me. Leaving one of the many fields that define the final miles of this race, a walker called out my name and wished me well, telling me he was a fan of my podcast, which was really flattering.
Although there are still a few steep climbs between Botley Hill and the end, the final 5km or so of the NDW50 is be pretty flat, and offers a serious opportunity to put in a proper kick to close out the race. Although I was starting to ache quite a bit, I was able to pick up the pace quite a bit in the endless stretch of empty fields that close out the race. In the very last of these, as I entered the field, I saw another runner far ahead. I briefly thought I might be able to catch him, but doing the maths it was clearly impossible – I would have to run about two minutes per mile faster to get to him before the finish.
Nonethelees, when the finish line rolled into view (you can see it from a mile out), I put pedal to metal and dropped below 5-minute kilometre pace. On the final road into Knockholt I picked it up even more, not wanting to leave anything out there, eventually crossing the line in 7:53 and change – 8th male, 9th overall.
Takeaways
It’s remarkable the difference a few years of good training can make. If you’d told me four years ago that in a relatively short period of time I’d crack the top ten at this race, I’d have been blown away. I’m super excited to see what the next few years have in store for me as a runner as I move into my athletic prime.
As much as I was happy with my strategic choice to hold back in the first half, I think I could afford to have lit a few more matches early on, and that’s where the biggest opportunity lies for me to improve on this race. As you can see by the chart below, I’ve always had a habit of sitting back and moving up through the field. I’d like to experiment with going out a bit harder in longer ultras over the next couple of years.
