The Conwy Valley in northwest Wales proudly boasts the highest concentration of utterly hideous climbs anywhere in the British Isles. That’s right – more than the Lakes, more even than the North York Moors. The sheer abundance of absolute killer roads on either side of the small, snaking river between Conwy in the north and Llanrwst in the south make it just about the perfect place for utterly destroying your legs.

The one minor downside is that half of the climbs – the ones on the western flank of the valley – are dead-ends. If, like me, you prefer your rides to be nice, flowing loops with no turning back, the nature of these roads will seriously clash with your route-plotting Feng Shui. Don’t let this put you off, though, as the challenges you will face and the stories you will be able to tell later make this a must-ride destination.

Map of a cycling route in Conwy

The long route, starting and finishing at Llandudno

(Image credit: Future)

Longer route:
Distance: 105km (65.2miles)
Elevation: 2,611m (8,520ft)

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the perfect warm-up before the far more savage challenges to come.

Dropping south into the valley, you ride to Tal-y-bont and turn right for the first of the day’s three max-difficulty climbs: Cwm Eigiau. This utterly unforgiving dead-end road pitches you abruptly into the heart of Snowdonia National Park. Once you’ve summited, you turn around, drop back into the valley, and steel yourself for Afon Du. Blink and you’ll miss its base opposite a small car park – but don’t, because what lies ahead borders on madness.

Man takes selfie

Simon Warren is a hill climb expert best known for his 100 Greatest Climbs series of books that covers the best cycling climbs from all over the world.

Officially (I measured it myself) it’s the second-hardest climb in the UK, narrowly beaten by Bamford Clough. At 700m-long, it averages 22% and ramps up remorselessly. No photos accompany this one – that’s because I wasn’t willing to risk riding it again, after the last time I did, I snapped a pedal clean in half, which was enough to make me swear I’d never risk my bike or my knees on its evil slopes again.

If you reach the top, descend with extreme care, as it’s lethal, before continuing south to Trefriw and the mighty Cowlyd. Out of the frying pan and into the fire, this is one of Britain’s great roads: a true giant stitched with hairpins and more 20%-plus ramps than you could dream of (or have nightmares about). An undisputed classic. At the top you may crave a breather in the peace and quiet, or perhaps at a cafe back in Llanrwst, before facing yet another bout of brutality: Melin y Coed begins so unrelentingly steep that you’ll question your life choices more than once. Mercifully, only a couple of climbs remain. First, just for good measure, the rise from Llanrwst up and around Pen-Bryn-Ddoged, and then, after the long, uneventful return to Llandudno, a fitting finale: the glorious hairpins of the Great Orme.

Man cycles up hill

(Image credit: Andy Jones)

strava.com/segments/27339622
KOM: Sam Stewart-Ball, 7:42
QOM: Kelly M, 16:32
Length: 1,589m
Elevation: 185m
Average gradient: 11%
Max gradient: 28%

It’s just as well there are beds at the top because you may want to check in when you get there. The most northerly of the ‘Conwy killers’, this dead-end to the youth hostel saves its hardest, 28% ramp for last.

2 Afon Ddu

Strava segment: strava.com/segments/27339644
KOM: Kieran Wynne-Cattanach, 4:55
QOM: Jess E, 8:55
Length: 691m
Elevation: 156m
Average gradient: 22%
Max gradient: 31%

Until Bamford Clough entered the conversation, this little road held the title of the steepest in Britain. Getting up it without stopping takes a Herculean effort, unless you are on a mountain bike with incredibly small gears – which of course is cheating!

Mountain and a cyclist

(Image credit: Andy Jones)

3 The Cowlyd

Strava segment: strava.com/segments/19678560
KOM: Ed Laverack, 12:33
QOM: Illi Gardner, 15:26
Length: 2,912m
Elevation: 378m
Average gradient: 12%
Max gradient: 20%

The Cowlyd is the king of the Conwy Valley, the climb that everyone comes to ride. With its stack of hairpins, its utterly relentless 20% gradients and of course the complete solitude of its empty summit, this is a place where you can scream to your heart’s content!

4 Bwlch-y-Ddeufaen

Strava segment: strava.com/segments/19678618
KOM: Dan Evans, 17:36
QOM: Illi Gardner, 20:59
Length: 5,459m
Elevation: 400m
Average gradient: 7%
Max gradient: 20%

Of the two climbs that leave Tal-y-bont, this is the easier. How can a 5.5km climb with slopes that touch 20% be easy, you ask? Well, compared to its neighbour the Cwm Eigiau, it’s just a puppy.

5 Cwm Eigiau

Strava segment: strava.com/segments/2113971
KOM: Dan Evans, 13:52
QOM: Illi Gardner, 14:58
Length: 3,604m
Elevation: 348m
Average gradient: 9%
Max gradient: 25%

Heading to the lake located at its eventual summit, this road is almost as brutal as the dreaded Cowlyd – almost. Packed with 25% bends, it’s all-out war on your legs for well over three kilometres until you can finally relax in the emptiness of the mountains.

man cycles up country lane hill

(Image credit: Andy Jones)

6 Grinllwm

Strava segment: strava.com/segments/19678672
KOM: Aiden O’Leary, 5:58
QOM: Illi Gardner, 6:50
Length: 1,391m
Elevation: 160m
Average gradient: 11%
Max gradient: 25%

This little killer out the back of Trefriw packs a solid punch right from the get-go. Be ready in your smallest gear and tighten your shoes as it ramps up to 25% almost immediately before twisting into the tree covered hillside.

7 Nebo Road

Strava segment: strava.com/segments/19678656
KOM: Sam Stewart-Ball, 13:12
QOM: Illi Gardner, 16:13
Length: 5,508m
Elevation: 282m
Average gradient: 5%
Max gradient: 9%

At last, a nice steady climb. The Nebo Road is a delight to ride: five beautiful kilometres of 5% gradient which never breach double figures as the road sedately makes its way out of the valley.

8 Melin y Coed

Strava segment: strava.com/segments/27339739
KOM: Kieran Wynne-Cattanach, 12:32
QOM: Illi Gardner, 16:46
Length: 3,131m
Elevation: 316m
Average gradient: 10%
Max gradient: 20%

No one in their right mind would choose this road over the sedate slopes of the Nebo Road next door. This one is torture: ramp after ramp of 20% leads to brow after brow.

9 Fford Llwyn Du

Strava segment: strava.com/segments/27339634
KOM: Jack Broadley, 7:29
QOM: Jess E, 14:21
Length: 1,624m
Elevation: 186m
Average gradient: 11%
Max gradient: 19%

Yet another climb with a double-digit average, this one hits you with three brutal ramps of stiff gradient – bang, bang, bang! One of a multitude of nasty ascents up the eastern side of the valley, it will keep you trapped in purgatory on its sinuous hedge-lined course from base to summit.

10 Sychnant Pass

Strava segment: strava.com/segments/19678542
KOM: Dan Evans, 5:19
QOM: Illi Gardner, 6:02
Length: 1,840m
Elevation: 147m
Average gradient: 7%
Max gradient: 17%

Not all the climbs in the region can be savage. Thankfully, there are a few like this beautiful twisting ascent, which, although touching 17% in places, is far more manageable than its near neighbours.

views of north wales

(Image credit: Andy Jones)