A very wet ascent and descent of each of the 6 main tracks to the Yr Wyddfa / Snowdon summit, which are: Llanberis, Pyg, Miners, Watkin, Rhyd Ddu, Ranger.
Profile:
The paths vary in terms of difficulty and how runnable they are, which plays into the order in which you may wish to complete this FKT. As long as you complete each of the 12 total pieces, no precise order is specified, and you do not need to start from the village of Llanberis (though for convenience I also have).
You will find differing rankings of what is considered the hardest/easiest path. There is excellent information and photos available from the official Welsh government site on Eryri / Snowdonia national park; you can decide according to your skills and needs.
Terrain varies - boulders large and small to climb over or around, large stone/slate to walk across, loose rocks, a bit of scree, a bit of boggy grassland, some dirt tracks / fire roads, staircases in various forms, and even a little bit of paved path.
Altitude is unlikely to be a factor as the summit sits at 1085m/3560ft. There are a few exposed ridges / large drops which may be uncomfortable. In good weather the paths are not overly physically challenging for a regular hiker.
When to go and preparation:
Your comfort with running at night, in high winds, and particularly in the rain should guide your planning. This FKT can be achieved entirely in daylight hours in the summer months, for example, and as early as the first days of spring depending on your fitness.
I would recommend April to September for weather and daylight reasons - from October onward, average precipitation increases. That said - the 'best' times will inevitably be the most popular times on the mountain. e.g. Llanberis and Pyg track are ridiculously crowded in summer peak or on bank holidays / weekends. Quite obvious, but do consider this.
What may delay you significantly on any given day is the strength and duration of storms, which can be frequent and fickle. Adapting to darkness or wet conditions will require you to carry (or resupply with) more gear and extra food/water.
Be aware that there are no mountain huts to sleep in, just a visitor centre at the summit with very limited hours, and a 'mountain railway' in the loosest possible terms. There are, however, 24-hour public toilets at the bottom of each path (with all but Ranger path offering drinking water taps).
My experience on the day:
Knowing it would rain every day I was visiting, I chose the day with the most 'pre-rain' time and left for the trailhead just before sunrise. It had rained most of the night before. Due to the rain I chose an order of Watkin, Rhyd Ddu, Pyg, Miners, Ranger, with Llanberis path bookending the effort.
The top of Watkin was still wet when i reached it (leg 2) and i was immediately glad for my choices as it's a technical descent at first. The only sunshine of the day was during this down-and-up. After taking the last of the viable photo breaks at the top of Rhyd Ddu, I was similarly glad to be handling its narrow ridge before any weather changes. Completing the descent of this 4th leg of 12 got me to the toilet facilities where the public water tap is. Back on up.
Before the end of leg 6 - Pyg descent - light rain had started, 2 hours ahead of schedule. Pyg track had already been wet from the night before so i'd had a chance to feel comfortable that my shoes would do the job once the rain really hit. Nevertheless, i resolved to wait until my other water/clothes change stop at the end of leg 8 (down Miners) to make the final decision if i needed to stop. Buses would still be running from that parking lot at Pen-Y-Pass back to Llanberis.
It was a pretty harrowing Miners descent. All the puddles on path had turned to rivers, and there were still quite a few hikers stuck out there, some not in a good way and all very very soaked like me. After hand-holding a couple of them down to the (finally!) flat bit of the path, I jogged for the first time in hours the rest of the way. I had a proper 24-minute rest stop to fill up my waters and change for both the rain and the night, and have a surprisingly glorious 2 crumpets i'd smashed together with massive amounts of Nutella for my "not long now" solid food treat. Again, back on up.
My fresh clothing lasted 20 minutes and the waterproof gloves an hour. For this FKT you go back to the summit every time - adding a horrible extra exposed mile on the top that was by now extremely windy, cold, rainy.. and hailing. Who knew forgetting my ski goggles would be such an error? Had literal eye pain from getting pelted up and down this top stretch and half of Ranger.
Saving the 'easiest' pair of down/up for last was a relief. Apart from the strong gales and a few stubborn cows on path, soon enough i made my last pilgrimage to the summit and turned to leg 12, Llanberis and a warm bed.. not before another hour of hail and rain in my face, naturally.
I knew what I was getting myself into (=suffering!), packed accordingly for weather and dark, and was pleasantly surprised and secure with the grip of my shoes on wet rocks, but really, truly -- if any of this makes your stomach drop or you haven't the experience with poor conditions, please don't be a bit crazy like i am :-) Always know when and where your potential stopping points are.
Thank you to all the hikers who saw me passing by twice or three times on the day and gave me a cheer :)
My supplies and FKT type:
I completed the FKT solo and Unsupported, carrying around 3500 calories (2600 in carb powder drink mix and 900 of solids - 4 Decathlon gummies, 1 pack of chews, and a Nutella-crumpet sandwich). I was carrying 3x500ml bottles, with public water refills of 1.5L and 1L.
I'm small and was moving slowly, but still disappointed not to finish what i brought - only the equivalent of 7 of 9 bottles and the Nutella sando - total 2400cal.
In addition to the above and hiking poles, my bag was full of extra clothing and night gear (waterproof trousers, longsleeve thermals, winter hat, extra socks and gloves, thicker waterproof gloves, 2 torches and extra batteries, emergency blankets, first aid kit).
I kept a waterproof jacket and buff on all day, overtop a T-shirt, shorts, arm sleeves and leg sleeves. Had the temps been much below 0 i'd have added a 2nd jacket to the mix; as it was, i was well happy with my thermals under my (normally excessively hot) waterproofs.
Future improvements on this FKT time:
I did not start out anywhere near race pace, rather always keeping a modest effort in anticipation of a long day of up to 20 hours. As the weather worsened I purposely slowed even more on the descents for safety. My total 'water station' time of 33 minutes would have reduced to ~15 in dry conditions.
A strong sub-elite female runner who is attempting this closer to a race effort and is good on messy downhills might come in at 14 hours, i.e. improve my mark by 3 hours.