Maerdy & Aberdare [ explore ]

Join me as I explore the fascinating Rhondda Fach Valley along NCN Route 881, from Tylerstown to Castell Nos. This was my fourth adventure up the valley and I was quite surprised to see how much had changed.
Overview: Maerdy & Aberdare [ explore ]
Date: July 29, 2021
Distance: 65.8 miles / 105.89 kilometres
Elevation: + 4336 / - 4336 ft
Duration: 9 hours, 17 mins.
If you ask most folks from one of the two Rhondda Valleys, they'll most probably not specify the difference between the Rhondda Fach and the Rhondda Fawr rivers (fach = little, fawr = big). "The Rhondda" is just a generalization people make here. It simplifies things. Yet these two rivers flow down two distictly different valleys before converging at the small town of Porth.

For my report today, I'll be focusng on the little Rhondda heading north from Tylerstown to Castle Nos Reservoir along NCN Route 881. The route is a combination of on-road and traffic-free paths, with some of the traffic-free sections being quite rough.

Once past the town of Maerdy, the route continues to climb for a couple of miles passing Castell Nos Reservoir to eventually join with NCN Route 47 high up on the Rhigos. From there, I turned east and climbed to the junction of A4233 (Maerdy Road) which I then followed down to Aberdare.
The Rhondda Fach begins in a marshy area on a high ridge called; Mynydd Beili Glas. At first, it's just a small stream which flows less than a mile before it is contained in Lluest-wen Reservoir and then again at Castle Nos Reservoir before flowing past the towns of Maerdy, Ferndale, Tylorstown, Ynyshir, and finally to its confluence with the Rhondda Fach at Porth.
Starting just outside Tylerstown, heading north, NCN Route 881 leaves the road and housing estates and becomes much more interesting as it turns directly into the woods.
Not far up the path there's a surprisingly small monument to the massive collieries that once stood along this valley. Cynllwyn Du Colliery (later named Ferndale) was a series of nine collieries that spread from Ferndale to Tylerstown.

The first shaft was sunk by Thomas Wayne in 1858, as it progressed it eventually became the deepest mine in the Rhondda Valleys at 554m (or over 1800 ft.). As a sidebar; there were a total of 79 collieries between the Rhondda Fach and Rhondda Fawr valleys. Here's the full list: Collieries of the Rhondda.

It's hard to envision this area with coal mining now. Everything is thick and green and overgrown. The last pit closed in 1959 and nature has done an amazing job reclaiming the land. Also, it's easy to see that we're following a disused rail line.
The path is smooth and wide as it closely follows along the banks of the river. There are a few muddy places, but mostly it is finely packed gravel and excellent cycling.
Then suddenly the path becomes very wide and even smoother! This is a new addition since my last visit. (I think this is near the Rhondda Fawr Leisure Centre?) It came as quite a shock to be honest and I was excited to see if this would continue up to Maerdy.
But no... it only lasts for about a half mile and then returns to a narrow path through the woods. It's still excellent cycling and to be honest, I kinda prefer being in the woods.
Then I reached an intriguing junction... I could continue straight on or cross this bridge and travel along a newly graveled section. What would you choose?

The mighty Rhondda is looking quite docile at this point (below).
I decided to cross the bridge and explore the eastern route just to see what the newer path had to offer... and it was surprising for just over a mile.
At Ferndale I passed a new community garden. It's nice to see the route getting more attention. But soon after that, the route suddenly moved back over to the western side of the river and into the woods once again.
It's lovely cycling through here. You just need to take your time. It's a bit rutted in places, but I had no problem on my road bike with 32mm tyres. (Gravel riders will love it!)
However, somewhere after Ferndale (and before Maerdy), I crossed back over the river yet again. I didn't record exactly where, but it soon turned out to be a bad choice. I saw that new gravel had been laid and wondered if it would be a better way?
It started out well enough, but soon the gravel became so large and deep that I simply couldn't cycle over it. I think even a mountain bike would have had difficulty. It was just too soft. I had to get off and push my bike for roughly a mile... almost all the way to Maerdy.
So after a mile of traipesing over loose gravel, I reached Maerdy and crossed yet again to the western side of the river. This is where the mighty Maerdy Colliery once stood.
Maerdy Colliery
Two shafts were first sunk in 1876 and by 1877 100 tons of coal were being hauled down the valley to Porth and Cardif, per day. By 1879 a third shaft was sunk which increased production to 30,000 tons per day. Then in in 1884, a fourth and final shaft was sunk which increased production to an astonishing 160,000 tons per day.
Unlike most collieries in Wales, Maerdy Colliery had a history of employing radicals as checkweighters and was well-known for its militant and communist associations. (Men such as Arthur Horner, a local communist, who at the time of his election to the South Wales Mining Federation, was serving a prison sentence for refusing to fight in the First World War.)
Ultimately in 1930, ongoning conflict with the SWMF and militancy directed toward the mine owners, led to the Federation expelling Maerdy Lodge from the organisation. During this dramtic time, the South Wales Daily News began descibing the colliery and town of Maerdy as "Little Moscow".

In 1947 the Colliery was assumed by the National Coal Board and redeveloped. Capacity for shafts 3 & 4 were expanded to 100 million tons of coal. By 1949 production was estimated to be sufficient to last for one hundred years.
During the 1950's and 60's, it was further transformed into one of the most modern pits in the United Kingdom incorporating new administrative offices, canteen, electrical winding-engine house, pithead baths, medical centre, and a huge coal washing plant.
After over 120 years in operation, the last miners descended to the pit bottom in December of 1990. The site was cleared in 1996 for a Fenner Industrial; a rubber polymer plant which sits just behind the trees to the left.
To read more about Maerdy and the collieries that once dominated this valley, check out: The Rhondda Valley Library Service, The Coflein Site Records, and of course; Wikipedia, Maerdy Colliery.
It's hard to imagine how this area once looked with the massive colliery. This small path from where the trains once ran is all that's left. The Fenner Industrial; a rubber polymer plant sits just behind the trees to the left.
A great read and lovely stop for lunch. (photo taken in 2016)
I then crossed Maerdy Road (A4233) to where there is a wonderful marker for the colliery (shown above). The path then becomes a paved service road leading up to Castel Nos Reservoir. Also, Castel Nos makes it's first appearance over the trees (below).
Although it is often thought to be a relic from the colliery, Castell Nos Filter House was part of the Rhondda Fach Water Scheme built c.1884-1900.
A few yards up the path and just ascross from the main dam is this blue plaque. They call it a "castle", but it's mostly just a knob sticking out from the hillside. Many folks don't know that this was once the site of a castle, but here's a quick read about it receiving landmark status.
Cycling around the eastern shore of the reservoir is lovely. The path is exceptionally smooth and flat. (I haven't been able to find much about Castell Nos reservoir itself.) In the photo below you can clearly see how Castell Nos commanded over the valley.
Then I came across this picnic table and bench just before the junction with NCN Route 47. This is a nice addition to the route and a perfect spot to stop for lunch.
NCN Route 881 ends at the junction with NCN Route 47, which continues straight as a paved path (shown below heading up through the valley). That route leads up to Lluest-wen Reservoir, a much larger and well documented reservoir.

However, turning right onto NCN Route 47 the path becomes un-paved and offers a steep climb up the adjacent hillside (shown below, as I've stopped to turn around and look back).
The gravel is quite loose and the hill is rather steep, so that selecting the right tack is crucial for the first few hundred yards.
This entire hillside was once a thick forest, but back in 2017 it was all cut for paper (I'm guessing?) You can see some images I took just after the trees were cleared in my gallery: Maerdy & Aberdare. I find it quite surprising that they didn't replant any trees, but perhaps they've left it open for the wind farm across the valley?
Soon the path levels off and the views open up. The reservoir is hidden, but Castell Nos stands out against the hillside (below). Can you imagine it? I know there's not much to go on now, but my mind races with the idea of a castle looming over the valley. It must have been very imposing.
Coming around the bend you can now see down the valley and the road coming up from Maerdy. I've seen cyclists climbing that hill, but I much prefer this longer and slower climb.
Looking back at the sign as I leave NCN Route 47 for the main road (above), it seems odd to call it St. Gwynno Forest... they've cut most of it down!
Meanwhile, Maerdy Road is lovely. There's an occasional car, but during the middle of the week and early afternoon; it's pretty desolate (as you can see!) Who needs gravel when the paved roads look like this?
I took nearly the same photo four years apart! (2017)
And that was that. I sailed down the hill into Aberdare where I joined NCN Route 478 which I followed back through Mountain Ash to Abercynon. From there I hopped on NCN Route 47 again and cruised back across the valley to home.

For additional info. with some lovely photos, be sure to check out Tracey Purnell's walking blog: Castell Nos and Lluest Wen Reservoir Walk from Maerdy
Summary - Maerdy & Aberdare [ explore ]
This was my fourth ride up the Rhondda Fawr Valley to Castle Nos. My overall ride for the day was much longer than the 14 miles I've documented here and I'm a little disappointed looking back at my photographic efforts.

I first cycled NCN Route 881 back in 2016, however on that adventure, I continued north-west on NCN Route 47 and cycled over the ridge, past Lluest-wen Reservoir. Once at the top, I came down the big hill into Treherbert and snaked my way home along bits and pieces of NCN Route 882. You can view that ride report here; Maerdy & Treherbert Tour.

I then returned to Castell Nos & Aberdare in 2017 and 2018 and traveled the same route I made for this report, however, in 2017 I only created a gallery of images: Maerdy & Aberdare. In 2018, I wrote a much more extensive report: Castell Nos & Aberdare which aslo includes some details about NCN Route 478 back to Abercynon.
At some point I think I should merge all these reports into a single — larger feature and possibly create a ride for my Routes to Ride section.

Although, the area has changed somewhat over the past five years and perhaps another trip where I avoid the deep gravel section would be worth considering? It's an interesting area which feels quite remote despite being rather accessable.

I hope you enjoyed this little write-up and as always, thanks for spending your time with me & Bike Wales.

Cheers! - muse kidd 
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