The Tumble (SW #97) Bike Climb - PJAMM Cycling

3.1 mi
1,250 ft
7.8 %



The Tumble is the second most difficult climb in Wales after Bwlch y Groes, and one of our favorite Welsh climbs. The climb is a good distance at nearly five kilometers and averages just over 8% average grade. There is a 2.5 kilometer 10.5% segment beginning 600 meters from the start that puts us to the test right away. 
7.8% grade for 4.9 kilometers with 0 descent.  The crux of the climb is 2.7 km beginning at 600 meters that averages 10%.  30% of the climb is at 10-15% grade.  The steepest 500 meters is 12%.

See more details and tools regarding this climb's grade via the “Profile Tool” button.
Roadway:  Two lane highway with center stripe and no shoulder for most of the climb.

Traffic:  Moderate.

Parking:  In the grass on the side of the road 44246 at the road to overpass the freeway 210 meters from climb start - MapStreet View (Directions), or drive across the overpass to the other side of A465 to park (Google Map) 350 meters from the start. 
Provisions:  None on the route but there are many options in Abergavenny, four kilometers northeast of the climb start.  
Before heading out on any cycling adventure check out our Things to Bring on a Cycling Trip and use our interactive check list to ensure you don't forget anything.
Use the “Routes in Area” button on the menu bar above to see other bike climbs in this area.  If cycling in this area you can choose from several different lodging options.

 See our 100 Greatest Cycling Climbs, Britain for other Wales climbs included in Simon Warren's book on cycling hills in the UK.  



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Cycling The Tumble, Wales - road bike leaning against a rock overlooking a small pond surrounded by brown grass and green pastureland, blue skies and hills in the distance,  Simon Warren 100 Greatest Cycling Climbs #97 logo in corner

Cycling The Tumble, Wales, UK.

Keeper’s Pond near top of climb.

The Tumble is the second most difficult climb in Wales after Bwlch-y-Groes, and one of our favorite Welsh climbs.  The climb is a good distance at nearly five kilometers, and averages just over an 8% average grade.  There is a 2.5 kilometer 10.5% segment beginning 600 meters from the start that puts us to the test right away.  

Cycling The Tumble, Wales - photo collage, rock monument atop hillside overlooking pastureland, boats parked along canal, pond along roadside surrounded by pastures, road carved along hillside, road sign for The Tumble, PJAMM Cycling logo in corner

This climb has been included in many British cycling events, which is obvious from the start, with a “Start of Climb” sign designating the beginning of the 2018 Iron Mountain Sportif and also a cycling summit sign at the climb’s finish.

Cycling The Tumble, Wales - sign for Iron Mountain Sportif 2018, Start of Climb

No question where climb begins.

Cycling The Tumble, Wales - Beacon Canal with house boats parked alongside it, green hillsides and blue sky, large green trees

Monmouthshire and Beacon Canal at 400 meters.

Cycling The Tumble, Wales - dense tree coverage over two lane road

Forest and tree coverage first third of the climb.

Cycling The Tumble, Wales - stretches of two lane road, white home along roadside, bright blue sky, small pond, PJAMM Cycling logo in corner

Views along the climb.

This climb is located in the eastern section of Brecon Beacons National Park, Wales (established 1957, 134,420 hectares/332,160 acres), which is the third of the three Welsh parks (the other two are Snowdonia and Pembrokeshire Coast).  Brecon Beacons NP covers a 519 square mile area between Llandeilo in the west to Hay-on-Wye in the northeast and Pontypool in the southeast.  In February 2013, Brecon Beacons received International Dark Sky Reserve status.  The park contains mostly grassy moorland where its common to see Welsh mountain ponies and mountain sheep grazing, but also includes forestry, valleys, reservoirs, waterfalls, and caves.  Because of the park’s remote location and the harsh weather in its uplands, Brecon Beacons is used as a site for UK Special Forces military training.  You can read more about Brecon Beacons National Park here.

Cycling The Tumble, Wales - Road sign for Y Tumbl, The Tumble, Summit 512 metres

That’s a wrap!

4.9 km at 7.9%.

Simon Warren writes of The tumble, it is “one of the most feared and frequently raced climbs in Wales.  The Tumble offers an excellent challenge to any rider” (100 Greatest Cycling Climbs, pp. 164-165).


Steepest kilometer begins at 700m (11.3%) writes of this climb:

“I was staying in Forest of Dean this weekend, so I thought I’d cycle out to the Tumble – a climb that has featured in many Tour of Britain’s and something I’ve watched quite a few times on the TV.

In theory, it was 25 miles from the Forest of Dean to the base of the Tumble in Govilon, Abergavenny. But, I trusted my instinct of ‘remembering the roads’ from five minutes of studying the map, rather than taking it with me. I once did the National 50 mile TT on the A40 around Raglan. But, that wasn’t much help, and I ended up taking a long detour on an unknown Welsh road to Usk. I kept hoping to cut across to Blaenavon, but didn’t have much luck. At one point, I went a long way up a mountain road to be greeted by a dead end sign – right at the end of the road. 40 miles later I did finally make it to Gavilon, and in between hail showers climbed up the Tumble.

It’s a good climb. The first half is a consistent 10% up a few hairpins, perhaps steeper in parts. As you go out of the trees, the gradient eases off a little and if there’s a tailwind you can pick up a little speed. It’s quite exposed at the top. It was popular with other cyclists, I must have seen a good 20-30 on various parts of the climb. I managed to overtake a couple on the way up. I had forgotten my cycling jacket so was just wearing loose under clothes, and had a camera swinging from thigh to thigh on the way up, which was irritating. I didn’t look the part, but still went up in a respectable time for February, on a winter training bike.”  Read more 

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