Katherine Moore

Ride in the footsteps of Romans across Wales — Sarn Helen

Nick Kaye (CC BY-NC-ND 2.0)

Ride in the footsteps of Romans across Wales — Sarn Helen

Mountain Biking Collection by Katherine Moore
4-7 days
3-5 h / day
190 mi
16,400 ft
16,400 ft

An ancient Roman road that divides Wales from north to south, Sarn Helen’s total and exact route and precise heritage is somewhat of a mystery. While many long stretches of gravelly doubletrack remain from the original, other sections have been paved into the modern road network, and some parts seem to have vanished altogether.

While the academic subject of the exact course of Sarn Helen is still debated, the brilliance of this route by bike is certainly not. You’ll need a mountain bike with wide, grippy tyres and a good range of gears to navigate Wales’ steep hillsides and the many sections of technical trail that you’ll find along the route. The course takes its name from Saint Elen of Caernarfon, a Celtic saint that is said to have ordered the construction of roads in Wales as far back as the 4th century.

From coastal castles to the steep pitches of Snowdonia National Park, mountain passes to the UK’s first trail centre at Coed-y-Brenin, traversing the ‘desert of Wales’ through the Cambrian Mountains and spectacular Elan Valley and lastly crossing the rough and wild Brecon Beacons National Park into the valleys of South Wales, there are few long-distance routes that rival the variety of landscapes that you’ll find on Sarn Helen.

Choose the spring or summer months for your attempt on Sarn Helen, where the ground will be less boggy and weather hopefully more favourable. This is Wales though, so make sure you always pack waterproofs and emergency equipment, as there are many remote parts of this route.

This Collection features the route split into seven stages, which you can ride each day, combine or split further as you wish. You’ll find places to stay, get more supplies and enjoy a hot meal in most of the towns and villages on the route, but it’s important that you book ahead for accommodation, especially in the busier summer months.

Transport to and from either end is made most simple by train, with stations in both Swansea and Conwy, although there is not a direct link between the two. You can take your bike on these trains, but do check if you need to make a reservation for your bike when you book your ticket.

On The Map

Tours & Highlights

    28.5 mi
    8.1 mph
    2,975 ft
    2,375 ft
    Expert mountain bike ride. Very good fitness required. Advanced riding skills necessary.

    Ease into the Sarn Helen with a 28 mile (45 km) stage, mostly flat to start with as you head out of Conwy south along the flatter landscape next to the river with the same name. Just over half the stage is this gentle introduction, before hitting the steeper inclines of Snowdonia National Park.

    It’s made easier by the fact that it’s also on the road, tarmacked all the way to the gateway to Snowdonia, Betws-y-Coed. Don’t let this fool you though, what is to follow over the seven stages is anything but easy.

    Take a short detour off the main route to explore Betws-y-Coed, a popular tourist destination thanks to the Steam Railway and numerous little shops selling everything from rock candies and local crafts to serious outdoor kit!

    After your pitstop in Betws-y-Coed, the real fun begins as you take the Sarn Helen track to the west of the village. With gradients of up to 46% on this monstrous climb, you’ll likely be walking your bike up this incline! After the short climb, you’ll reach the plateau, riding along the chunky gravel of this roman road surrounded by expansive views.

    You’ll descend off the moorland gravel road to Pont-y-Pant, where you can relax with a short stint along the flat road alongside the Afon Lledr to Dolwyddelan. Then it’s time for the second climb of the day, heading up the remote Cwm Penamen valley to start before the more sharp Sarn Helen doubletrack leads you up to Cwt-y-Bugail Quarry.

    Rejoin the doubletrack on the other side of the slate mine to enjoy the descent for the rest of the stage to Llan Ffestiniog, more gradual than the mountainside you’ve just tackled. You’ll join a lane to descend down the Cwm Teigl valley to the village. There are a couple of hotels, bunkhouses and guesthouses to stay in here, as well as a campsite a little out of the village.

    20.8 mi
    8.9 mph
    1,450 ft
    2,025 ft
    Expert mountain bike ride. Good fitness required. Advanced riding skills necessary. Some portions of the Tour may require you to push your bike.

    The second stage of the Sarn Helen route is a brilliantly fun day on a bike, and one where you’ll be glad of your fat rubber and wide gearing as you pass through Britain’s first trail centre at Coed-y-Brenin. Covering no less than 21 miles (33.5 km), you’ll head south through the spectacular Snowdonia National Park to the quaint town of Dolgellau.

    Despite the mountainous terrain, there’s not a huge amount of climbing in this stage, and it’s all in the first half too. From Llan Ffestiniog, you’ll start by following the road past Bont Newydd, before turning onto the smaller lanes to climb the lower slopes of Mynydd Maentwrog. Descend a little to the impressive Tomen Y Mur Roman hill fort complex, taking the singletrack trail that widens to deliver you to the shores of Llyn Trawsfynydd.

    There’s a short stint along the main road here before veering off to the left onto a smaller lane that leads you into the heart of Coed-y-Brenin Forest Park. You’ll climb as the paved road gives way to a crumbling gravel track, passing nearby the summit of Craig Y Penmaen, where you’ll enjoy wide and stunning vistas.

    Next you’ll drop down the valley and straight onto the Coed-y-Brenin trail network, riding the rocky ‘Beginning of the end’ section down to the trail centre and cafe. Of course if you’d rather not opt for this pretty challenging built trail and features, you can always follow the many fire roads here for a less bumpy ride!

    After an unmissable visit to the cafe here, you’ll spend the rest of the stage gently descending to Dolgellau, taking the quiet lane alongside the Afon Mawddach past Llanellytd and along the cycle trail at the side of the main road into the town. A real honeypot town, you’ll have plenty of choice when it comes to places to stay and enjoy a hearty meal in Dolgellau, and the bakery is highly recommended!

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  • Difficult
    31.0 mi
    7.8 mph
    3,550 ft
    2,875 ft
    Expert mountain bike ride. Very good fitness required. Suitable for all skill levels.

    Wave a fond farewell to Snowdonia National Park as you exit to the south on stage three, heading deep into the Cambrian Mountains via the bustling town of Machynlleth, and along one of my all-time favourite gravel roads.

    There’s more than double the amount of climbing on this stage compared to the previous, totalling 3,543 feet (1,080 metres) over 31 miles (50 km), so ready the climbing legs! There’s little time to warm up as you exit the town of Dolgellau, straight up the steady climb to Tabor and contouring around Pen Y Bwlch-Coch.

    At the end of the lane, you join the cycleway that’ll pave your way almost all the way to Machynlleth. This is a really curious way, firstly dropping down to the main road before the narrow strip of tarmac heads straight up a mountain pass away from the road, through the middle of a grassy sheep field. After this steep climb, you’re greeted with excellent views of North Wales before sailing down the other side to the pretty settlement of Aberliefenni. From here it’s all back lanes to Mach, finishing with a little cycle lane to take you over the river and into the town.

    There’s plenty of great places to stop for a while in Mach, from the many pubs to vegetarian cafes and corner shops. Make sure you stock up plenty, as the next part of the stage is pretty remote, and exceedingly delightful.

    Follow the lanes out of Machynlleth to start with, through the middle of the golf course and through Forge. The lane ramps up steadily as you start to climb under shady broadleaf trees, becoming more and more remote the closer to the peak of Mynydd Bychan you get. A series of long, steady gravel switchbacks next, as you climb through the forests and up onto the moorland over rocky gravel roads.

    I like to call the next bit ‘little Scotland’; it’s about as remote as you can get for Wales, and in places there’s nothing man made as far as the eye can see, bar the wide and rugged trail of course. The gravel doubletrack is anything but tame, with deep water-filled ruts almost year-round and boulder-like patches to negotiate. With Nant-y-Moch reservoir to your right, continue past the river crossing to the gate where you’re rewarded with silky smooth tarmac for your next leg.

    Cruise down to Ponterwyd amid classic Mid Wales scenery to finish the stage, where you’ll find a great place to restock at the petrol station on the main road. There are a couple of small guest houses nearby, but if you need more selection, then head onto Pontyfrynach.

    23.8 mi
    8.8 mph
    2,200 ft
    2,225 ft
    Intermediate mountain bike ride. Good fitness required. Suitable for all skill levels.

    It’s a straight-forward start to the fourth stage, which crosses more of the Cambrian Mountains and through the Elan Valley to Rhayader. They call this region the ‘desert of Wales’ for the lack of population and facilities, so make sure you’re well stocked up for this one. Start by following the scenic main road to Devil’s Bridge, or Pontarfynach, where you might want to explore the waterfalls for a while, especially if you’re a ‘Hinterland’ fan!

    After your gently undulating start, now you’ll fire up the legs with a road climb up to Hafod’s Arch, before sailing down the other side to the Ystwyth River. Here you join the same way as the Trans Cambrian (more at komoot.com/collection/899090/welsh-border-to-irish-sea-bikepacking-trans-cambrian-way) for a while on the road, passing the Cwmystwyth Mines.

    Where the Trans Cambrian splits off to tackle the Mohican Road, the Sarn Helen stays on this modern road across the open moorland. A few short climbs and descents but mostly pretty flat, you’ll leave the road at the highest point to join a rocky doubletrack to descend into Rhayader.

    The first town on the River Wye, you’ll find plenty of places for eating, drinking and resting here, as well as a bike shop if your bike needs any TLC or spares.

    38.5 mi
    9.0 mph
    3,125 ft
    3,375 ft
    Expert mountain bike ride. Very good fitness required. Suitable for all skill levels.

    From the edge of the Cambrian Mountains to the Brecon Beacons, stage 5 is the longest stage at 38.5 miles (62 km). Apart from two main climbs, out of the Elan Valley and later up Pennau Hill, the route is fairly easy-going.

    From your start in the town of Rhayader, head south-west to Elan village, perhaps stopping at the visitor centre and cafe there for a great cuppa and snack. You can take the traffic-free Elan Trail alongside the road and Caban-Coch Reservoir, crossing the beautiful bridge to continue on the road on the other side.

    When the reservoir ends, take the doubletrack gravel road up the side of the mountains between Drygarn Fawr and Gorllwyn, out of the Elan Valley, hitting gradients of up to 13%. It soon turns to singletrack as you navigate the pass, sailing down the other side to Beulah on doubletrack and small lanes again.

    Enjoy some flat respite across the river floodplains on smooth roads to Llangammarch Wells, changing direction to north-west. Here you’ll take the steep road climb up Pennau Hill, and then cross the upland area named Mynydd Epynt. You’ll stick to the road, joining the River Honddu and staying quite high up, gently descending all the way to the end of the stage in Brecon. This is the gateway to the Brecon Beacons to follow, and boasts many places to stay and refuel after undoubtedly a long day in the saddle.

    28.3 mi
    7.2 mph
    2,525 ft
    2,650 ft
    Intermediate mountain bike ride. Good fitness required. Advanced riding skills necessary.

    The penultimate stage of the Sarn Helen route will take you across the wild and isolate Brecon Beacons National Park, over the Fforest Fawr, along ‘the road to hell’ and through forestry to Crynant in the Dulais Valley.

    With incredible views of Pen y Fan to start, you’ll head south-west out of the town of Brecon on a small lane which you can soon turn off of onto a gravel track to the National Park Visitor Centre. You’ll transition to singletrack, then another lane and back before you meet the well known Sarn Helen track that crosses the Fforest Fawr, a wide a twisting gravel road that’s anything but straight! You’ll climb very gradually as it contours around the peaks rather than head straight over them, offering incredible views and probably a red kite or two soaring overhead.

    Over the tops and passing between the peaks of Fan Llia and Fan Nedd, start to descend gently now over the other side. You’ll reach what some call ‘the road to hell’, in fact a rather lovely gravel road if you ask me! Look out for the ancient Maen Madoc standing stone, cross the Nedd Fechan and continue along the edge of Coed y Rhaiadr down to Banwen.

    You’ll climb up from the village for the final part of the stage next, along one of the many byways through Maesgwyn Wind Farm, topping off your climbing at the peak of Hir Fynydd. From here it’s downhill all the way to the end of the stage, at first gentle forest tracks that become more steep as you approach the village. When you’re finished, there are just a few small places to stay here, but much more selection up and down the valley for accommodation and places to refuel.

    19.0 mi
    11.3 mph
    575 ft
    900 ft
    Easy mountain bike ride. Great for any fitness level. Suitable for all skill levels.

    The final stage is a short 19 mile (30.6 km) ride to Swansea, which should give you plenty of time to enjoy a celebratory meal by Swansea Bay and arrange any onward travel. You’ll mainly be off the roads too, as there’s a brilliant traffic-free cycle network into Swansea from the Dulais Valley.

    First up on the menu today, you’ll need to cross into the next valley to Ystalyfera, which
    is a very gradual climb on the road around the hill, to avoid a more brutal up and over. From here it’s plain sailing along the cyclepath, which follows the River Tawe south to the next town, Pontardawe. Here you swap onto the Swansea Canal, another serene and traffic-free cycle route alongside the water and under the shady leaves of trees. It’s very flat indeed as you head to Swansea through Coed Gwilym Park.

    Rejoin the banks of the River Tawe for the final stretch, an easy cycleway to follow that takes you alongside the pretty Fendrod Lake on your way into town. You’ll avoid the hustle and bustle of the main roads here which can be quite busy, as well as benefit from the rich wildlife alongside the river.

    After White Rock Park you’re nearly in the centre, but you’ll stay on the other side of the river until the docks where you can amuse yourself with the names of the many sailboats moored here, and head to the bay for a much needed recovery meal and celebratory drink! Follow the local cycling signposts to get to the central train station in Swansea, which are all very well marked and easy to follow.

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Collection Stats

  • Tours
  • Distance
    190 mi
  • Duration
    22:28 h
  • Elevation
    16,400 ft16,400 ft

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Ride in the footsteps of Romans across Wales — Sarn Helen