Cycle Network Route-8, known as the Lôn Las Cymru, runs over 400 km (250
miles) between Holyhead on Anglesey and Cardiff or Chepstow, and is reckoned
to be one of the toughest routes of all the Network. In its original form,
the way-marked trail offered a number of route alternatives along its
length, and at the heart of a number of decision points, the town of Dolgellau
had Route-8 markers leaving in four different directions. The two Route-8s
(or should that be Routes-8) heading north from Dolgellau converged just
east of Porthmadog, and those heading south met at Machynlleth. Fortunately
wisdom has prevailed, and this confusing situation has been remedied by
the renaming of the thread of trail running through Trawsfynydd/Dolgellau/Tywyn
as Route 82. Either way, this leaves Dolgellau on the Mawddach estuary
at the centre of a cycleway-drawn number 8, the 160 km long ‘Mawddach
Big 8’ (MB-8).
MB-8 makes use of quiet back-roads and tracks, although there are a few
forays onto busier roads. The tracks, although rough in places, involve
no technical mountain biking and with care should be passable on a hybrid
bike or tourer. The roughest of these is probably the Ffordd Ddu on the
South Loop. Having said all that, this is not a route for the faint-hearted,
as the distance alone will testify; each of the routes leaving Dolgellau
to the north or south is graded as strenuous, and each loop of the MB-8
consists of two of them! Add in over 4,500m of climb along the way, and
the scale of the challenge starts to take shape.
For a rider to be considered as one of the MB-8 elite, the journey should
be done as two back to back 1-day rides, the North Loop and the South
Loop. Double-Loopers will do them back to back on the same day. Of course,
mere mortals are also welcome, and are encouraged to break up the journey
as required. The MB-8 is one of the component activities of the Mawddach
Big Adventure, a multi-day, multi-activity challenge.
Dolgellau, at the meeting point of the two loops, is a logical starting point, although Penmaenpool, Barmouth or indeed anywhere along the Mawddach estuary would make an excellent base for tackling the challenge. The estuary boasts a wide range of bike-friendly accommodation to suit all pockets, as well as some seriously good places to eat and drink. As the route constantly dips in and out of small villages, there are shops and pubs along the way that will be glad to help refuel weary legs
The route is way-marked with blue and red National Cycle Network Route-8
and 82 signs but we recommend you carry suitable maps as a back-up. The
North Loop is covered by OS
Landranger Map 124, while the Southern Loop is on OS
Alternatively, Sustrans offer a 1:100K Route 8 North map which includes the entire MB-8 and more.
Those of a strictly road-biking persuasion (or even in a car) can follow
the loops formed by the A 496 and A 470 to the north, and A 493 and A
470 to the south. Be warned that these narrow roads can be very busy in
the holiday season. The A-road route is slightly shorter at just over
150 km, with just over 4000 m of climb. Don’t try doing the actual Route-8
in a car; bits are on tracks not open to traffic, many of the roads are
very narrow and steep, and the whole thing was originally laid out to
give cyclists a relatively traffic free experience.
FREE GPS DATA: Big-8 North Loop Anquet | Big-8 North Loop GPX
FREE GPS DATA: Big-8 South Loop Anquet | Big-8 South Loop GPX
In addition, a Mawddach Big-8 guide book is available to buy which contains further route details, background information and historical detail. This can be a bought as a printed booklet or an electronic pdf file:
THE MAWDDACH BIG 8
CYCLE ROUTE GUIDE
THE MAWDDACH BIG 8
CYCLE ROUTE GUIDE
An electronic (adobe pdf) route guide to the Mawddach BIG-8 will be emailed to you within 48 hours.
A bound, A5 booklet version of the BIG-8 route guide will be dispatched to you by first class post.
inc UK P&P
15 km (9.5 miles)
A flat and friendly there-and-back route following the old railway line along the Mawddach estuary. More...
23.8 km (14.8 miles) 501m climb
A circuit taking in the the Mawddach trail and the beautiful Cregennen lakes. More...
35.5 km (22.1 miles) 1040m climb
A Regional Cycle Network way-marked route out of Dolgellau, making use of quiet back roads and straightforward off-road tracks. More...
48.8 km (30.3 miles) 1260m climb
The Snowbikers Cadair Idris Challenge makes use of quiet back roads and some rougher off-road tracks to make a circuit around Cadair Idris. More...
78.9 km (49 miles) 4500m climb
A big road ride taking in the remote moors at the back of Coed y Brenin. More...
160 km (99.4 miles) 4500m climb
An epic 2-day ride. Following National Cycle Network Route-8 in a figure of 8, with the Mawddach estuary at its centre, you will ride for around 8 hours and cover around 80 km each day. Its octastic! More...
+250 km (+155 miles)
A journey of over 250 km, on foot, cycle and mountain bike, that will take you through some of the most beautiful parts of southern Snowdonia. More...
World class trail-centre mountain biking with 7 different trails to chose from. Trail heads and visitors centre 12 km from Dolgellau. More...
Short but sweet trail centre mountain biking. Trail Head 19 km from Dolgellau. More...
Real trails with a trail centre feel. Trail Head 25 km from Dolgellau. More...
The annual early season mountain bike event to challenge you after the dark winter months, and a good warm up for the new year ahead. More...
The area has a network of rights of way across the hills that are open to mountain bikes. If you are unsure where a mountain bike is entitled to ride, or would prefer not to have to navigate, consider getting a local guide to do the work for you. More...