Cycling YouTuber Katie Kookaburra decided to take on the toughest 100km in the UK. The brutal 100km route included more than 3100m of elevation and 21 steep climbs.

Katie Kookaburra headed over the Pennines to Sheffield to take on the toughest 100km in the UK. The route included more than 3100m of elevation and included 21 of the most brutal climbs. Here, she talks about her day in the saddle

I love a climb, long, short, steep, shallow... I just love getting me and my bike up them. So, when I was asked by Rapha to create and take on the toughest 100km in the UK, as part of their Women's 100 event - I jumped at the chance.

I started plotting different routes where I thought the hardest 100km would be. So I naturally headed to the Yorkshire Dales, Peak District and Lake District. After a bit of searching online, I found exactly what I was looking for. The toughest 100km had recently been uncovered by a local bloke in Sheffield by name of Mark. He had plotted the brutal route that took in 21 climbs. Yep, 21 of them! This was part of a competition that the Instagram account Band of Climbers had set up in order to find the toughest 100km. The only rules were:

1. The route had to start and finish at the same place
2. The route could not criss-cross or double back on itself
3. The route must not use any part of the same road twice
4. The route must be on-road at all times (no gravel)

The tough route Mark created adhered to these rules, so there was only one thing for it... get my bike over there.

The route featured some popular climbs such as Pea Royd Lane, Cote de Bradfield and Burbage Moor. As well as heading down The Strines - which I was pretty happy about. These are three steep, consecutive, climbs and the last time I rode them a few years back I couldn't believe the steepness of the switchback on the final corner.

On a dry but chilly Sunday morning, I set off for Sheffield on my Endurance SL. Mark actually came out to join my friend, Nicky and me, for the first part. Predominantly, to keep us company and tell us about the pain that was about to explode through our bodies as we weaved up these monster climbs.

We met at the Lovely Pear cafe and off we went - uphill. It was 10% for around 1.4km and then the next climb, and then the next. Mark happily told us that there was only 3km of flat roads along the entire route. So, for 99.7% of the ride, we would be going up, or down.

At the start, it felt like we were wending our way up and down adjacent roads just to get in that elevation and so I completely lost my bearings. These climbs were just residential roads at first then we headed out into the open moorland.

We then arrived at Wheel and Lumb Lane - a 2.9km climb, averaging 9% and one of the longest of the day. It was at this moment, my friend Nicky realised her rear tubeless tyre wasn't doing its job - and was running at about 40psi - not ideal for a day in the hills.

New Mill Bank was next and was pretty steep at 13% for 1km. Then we headed towards Pea Royd Lane. This was featured in the Tour de France route when Yorkshire hosted the Grand Depart. It was good to know that these roads had been climbed and graced by the greats.

Pea Royd was windy and steep, but such a great one to have a blast up. It has also been the climb of choice for several hill climb competitions, including the British National Championships a few times. Make sure your legs are prepared for that if you decide to take on the route. Stats wise, it's just over 1km with an average of 15% and max gradient of 20%.

We headed on into the beautiful countryside, dipping between the trees on the descents and emerging into the open scenery on the tops of the climbs. These are some great roads if you fancy testing your climbing skills. As we took a breather somewhere in between some hills (after the tenth hill you kind of forget where you are) we bumped into a cycling club who were doing the same route but in reverse. The accolade of the toughest 100km in the UK is definitely getting us roadies amongst the gradients.

Then we arrived at what was for me the toughest climb of the day - Cote de Bradfield. This one seemed to go on for so long, yet was only 1.9km with an average of 10%, But, to be fair, it did top out at 18%, so that's probably why it felt like such a brute. Or maybe it was just the accumulation of 50km and around 2000m in the legs. Either way, it was tough!

We stopped in Hathersage for a quick bite to eat - or in Nicky's case, two bags of nuts, a pot of pasta and a bottle of orange, before we ventured up Burbage Moor. This fairly long and hilly route took us literally back onto the road from Hathersage, around 500m up the road. But the views were worth it.

Just as we had finished the toughest hill of the day - the tubeless tyre gave out. No amount of air was getting it back up so Nicky admitted defeat and chucked in a tube. Tubeless are great when they work but if all else fails, get that tube in there.

Luckily we had two fellow cyclists stop and ask if we needed help. This included the cycling club who had done the route the opposite way and were in their car on the way home. Had we been at the roadside THAT long? Well, this was going to be the longest 100km we had done, so what's a half-hour at the side of the road laughing at ourselves struggling with a less-than-ideal tubeless setup.

So sealant cleaned up, tube in the tyre, we set off on the final steady 10km back to Sheffield. We got our heads down, stuck it in high gear and off we went.

As we arrived back to the start, we both agreed Cote de Bradfield felt the toughest of the climb but it was well worth it for the epic route.

It's definitely worth a visit to Sheffield if you get the chance, as the roads were great, not too much traffic and of course, the hills were relentless.

My tip if you do decide to ride it, go for low gearing. Oh and take a spare tube or 2!

Here is my route from the day if you fancy having a go yourself.

Also if you want to watch us struggle up the climbs here is a video of the day.

https://youtu.be/bLr-J-_iwPg

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