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



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

  • Map data © OpenStreetMap contributors
    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 …

  • Difficult
    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 …

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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 …

  • Intermediate
    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 …

  • Difficult
    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 …

  • Intermediate
    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 …

  • Easy
    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 …

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Questions and Comments


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

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