The Bangor to Bethesda leg of the Snowdonia Slate Trail is a wonderful introduction to Snowdonia and its slate heritage. Starting from the sea, it provides easy walking with interest throughout as the mountains are approached.
NOTE: Lon Las Ogwen is closed 9/10/23 until 15/1/24 while the Council replace two footbridges. We suggest you start the Trail at Llandegai.
Starting at Porth Penrhyn, follow Lon Las Ogwen along the old Penrhyn Quarry Railway, running alongside the high walls surrounding Penrhyn Castle, before branching off along the North Wales Path past Cochwillan Mill to Cochwillan Farm. After tracing the route of the Afon Ogwen to Halfway Bridge, take field paths, tracks and lanes to Llanllechid Church.
Around the church, the Public Right of Way passes through a private garden. It is recommended that walkers divert through the churchyard, which the Church authorities are very happy for people to visit. This diversion commands exceptional views of the Carnedd and Glyder ranges, and the churchyard contains impressive examples of slate carving on gravestones and the sundial, along with a very attractive avenue of ancient yew trees.
From Llanllechid, follow minor roads before crossing the open mountainside below Moel Faban. With opening views of the Carneddau and Glyderau before you, and the extensive blue spoil tips of Penrhyn Quarry, take the footpath down to Hen Barc, and drop down into Bethesda along footpaths and through winding streets.
An overview of the section by Vicky Anne Jones
Note: Bullet point no 2 on page 32 of early editions of guidebook has an error. When you reach the A55, turn left, keeping the A55 on your RIGHT. This has been updated in subsequent editions
Note that Ymddiriredolaeth Llwybr Llechi Eryri – Snowdonia Slate Trail Trust is not responsible for third party websites.
Along the way
In the early days of slate quarrying, slate was shipped out from Aber Ogwen, the estuary of the river Ogwen, a few miles east of Bangor. This estuary was shallow and the smaller boats had a limited carrying capacity of some sixty tons. This constraint was overcome when, in 1790, Lord Penrhyn built Port Penrhyn on the river Cegin estuary. Penrhyn quarry operated its own fleet of slate-carrying ships.
Although a smaller operation at the port produced 133,000 school writing slates back in 1778, a factory was established in 1798 to mass produce such slates.
The port is home to a very unusual listed building. This circular toilet block boasts ten seats.
Lôn Las Ogwen cycle path
This highly attractive cycle path takes you, in just 11 miles, from the coast, through varying scenery, and into the heart of one of Snowdonia’s most dramatic mountain landscapes. For more information visit
Penrhyn Quarry Railway
The Penrhyn Quarry Railway first opened in 1798 as the Llandegai Tramway. It became the Penrhyn Railway in 1801 although on a different route.
Constructed to transport slate from Lord Penrhyn`s slate quarries at Bethesda to Port Penrhyn, the new railway was around six miles long and used a gauge of 1 ft 10.75 in.
It was one of the oldest narrow gauge railways in the world and closed in 1962. Its engines were dispersed: Blanche and Linda now run on the Ffestiniog Railway and Charles is on show in Penrhyn Castle.
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Penrhyn Castle was built between 1820 and 1833 for George Hay Dawkins Pennant by the famous architect, Thomas Hopper.
Known for his unorthodox style, Hopper opted not to follow the fashion for Gothic architecture. He went against the grain, choosing a neo-Norman design. Hopper’s hands-on approach also meant he oversaw the designing and building of the castle’s furniture, made by local craftsmen.
In 1840, with the castle finished, George Hay Dawkins Pennant died. His daughter, Juliana, inherited Penrhyn. She, in turn, married Edward Gordon Douglas, who later became the 1st Lord Penrhyn of Llandegai.
This mill treated wool for textiles and used sulphuric acid, which polluted the river Ogwen and poisoned the fish. This was not to Lord Penrhyn`s liking so he bought it and converted it into a corn mill. It closed in 1955 and became the home of Mr Vernon Barker – a talented woodworker who made furniture. He built the mill wheel, which was so finely balanced that the cat would turn it with its paw.
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The Church of St Llechid is a Grade II listed building. It was built to replace a much earlier 15th century church, the building dates from 1844.
Llechid was a 6th-century saint of Wales. Born about 556 AD in Brittany, she was the child of Ithel Hael de Cornouaille and an unknown mother. Her family moved to Wales, where many of her siblings founded churches. She is the Patron Saint of Llanllechid , where she built a Church and where a holy well (now lost) was attributed to her.
There is a legend relating the building of the original St. Llechid’s Church and the following account of it comes from Elias Owen’s ‘Welsh folk-lore: a collection of the folk-tales and legends of North Wales’ (1887)
There was a tradition extant in the parish of Llanllechid, near Bangor, Carnarvonshire, that it was intended to build a church in a field called Cae’r Capel, not far from Plasuchaf Farm, but it was found the next morning that the labours of the previous day had been destroyed, and that the materials had been transported in the night to the site of the present church. The workmen, however, carried them all back again, and resumed their labours at Cae’r Capel, but in vain, for the next day they found their work undone, and the wood, stones, etc., in the place where they had found them when their work was first tampered with. Seeing that it was useless fighting against a superior power, they desisted, and erected the building on the spot indicated by the destroyers of their labours.
A slate sundial in the churchyard of St Llechid.
Carneddau and Glyderau
What can you say about these mountain ranges? Absolutely wonderful. We leave it to you to experience these mountains on the walk.
At the end of the nineteenth century, this was the world’s largest slate quarry; the main pit is nearly 1 mile (1.6 km) long and 1,200 feet (370 metres) deep, and it was worked by nearly 3,000 quarrymen. Penrhyn is still Britain’s largest slate quarry but its workforce is now nearer 200.
The quarry holds a significant place in the history of the British Labour Movement as the site of two prolonged strikes by workers demanding better pay and safer conditions. The first strike lasted eleven months in 1896. The second began in 1900 and lasted for three years. Known as “The Great Strike of Penrhyn” this was the longest dispute in British industrial history. From 1964 until 2007 it was owned and operated by Alfred McAlpine PLC.
In 2007 it was purchased by Kevin Lagan (an Irish businessman and the owner and chairman of the Lagan Group) and renamed Welsh Slate Ltd which also includes the Oakeley quarry in Blaenau Ffestiniog, the Cwt Y Bugail quarry and the Pen Yr Orsedd quarry.
The quarry is home to Zip World Velocity, the fastest zip line in the world and the longest in Europe. This adventure takes you on the Little Zipper to build your confidence before you journey up the quarry on their famous red trucks. You will then descend down the Big Zipper over the quarry lake often reaching speeds well in excess of 100mph.
Bethesda is the first significant centre of civilisation encountered on this walk, with shops, cafés and pubs. Visit Caffi Coed y Brenin for a snack and support this social enterprise. The café has been part of Agoriad who provide training and assistance with the employment needs of people with learning or mental health difficulties, and has a reputation for being a favourite for the residents of Bethesda, for friendly service and good food.