In the rugged hills of Eryri (Snowdonia), an imposing stone wall stands as a testament to both Welsh craftsmanship and the financial mismanagement that marked one of the 19th century’s most notable white elephants. The leaning structure, known locally as Eryri’s “wailing wall,” stretches almost 60ft and boasts a cantilevered overhang of 1.5 metres. Remarkably, this architectural marvel has weathered nearly 170 years without a single stone shifting – a stark contrast to the ill-fated enterprise that funded its construction.
Gorseddau Quarry, perched above Cwmystradllyn reservoir near Garndolbenmaen, represents a chapter in the slate industry’s history marked by grandiose ambitions and unfortunate outcomes. During the 19th-century slate rush, Gorseddau sought to tap into the wealth that quarries like Penrhyn and Dinorwig were enjoying. However, the quarry never turned a profit and closed its operations in 1867, leaving behind a legacy of financial ruin.
One of Gorseddau’s distinctive features is the massive dry stone wall, standing as a sentinel against the backdrop of the dramatic landscape. This wall was a response to the challenge posed by a narrow-gauge, horse-and-gravity tramway connecting the quarry to Porthmadog. As waste tips accumulated along the tramline, threatening potential disruptions, the ingenious solution was a cantilevered wall designed to shield passing trains from falling debris. This innovative design later influenced the construction of the São Paulo Railway in Brazil.
Contrary to its appearance, the overhanging wall, according to Coflein, was intended to be part of a corbelled archway protecting the tramway. Originally envisioned as a tunnel, this ambitious plan was never fully realised. The quarry, backed by substantial capitalisation, implemented a tiered gallery system akin to the successful Penrhyn Quarry. The incline, drainage adit, blast shelters, and slate-makers’ gwaliau showcased the scale of Gorseddau’s aspirations.
A notable feature of the quarry’s infrastructure was the Ynys y Pandy slab mill, located 1km down the valley. Though now resembling a ruined abbey, this multi-storey building once housed a 26ft water wheel and showcased architectural ambition rare in the Welsh slate industry. The mill, dubbed Eryri’s “slate cathedral,” highlights the paradox of grandeur within the context of an ultimately futile industrial endeavour.
The village of Treforys, constructed for quarry workers on the opposite hillside, paints a poignant picture of misplaced planning. Established in the 1850s, this model village, named after its owner Robert Morris Griffith, offered little sustenance on the barren and rocky hillside. Disease and harsh living conditions led to its abandonment within a decade, earning it the moniker “a sort of Johannesburg” – a lawless and wild place.
Gorseddau Quarry began its small-scale operations in 1807, but significant development occurred in 1845 when entrepreneurs Robert Gill and John Harris secured a 63-year lease on the land. Despite raising substantial capital, the quarry struggled to turn a profit, with output peaking in 1860 and closing its doors in 1867. The subsequent liquidation of the Bangor & Portmadoc Slate and Slate Slab Company in 1871 marked the end of Gorseddau’s brief but costly existence.
Today, the quarry’s infrastructure, including the shell of Ynys y Pandy, stands as a well-preserved reminder of a bygone era. The Eryri National Park conserved the mill in 1981, allowing visitors a glimpse into the grandeur and folly of Gorseddau Quarry. A former school building near Cwmystradllyn reservoir has been repurposed as Tyddyn Mawr Tea Room, offering a warm welcome amid the remote surroundings. Despite its closure for winter, the place remains a testament to the enduring spirit of the area.
For those interested in exploring Gorseddau Quarry’s remnants, there’s limited parking by the reservoir. A scenic walk along the old tramway, past ruined farmhouses towards Treforys barracks and the abandoned quarry, provides a tangible connection to the past. Alternatively, a footpath around the reservoir leads to the hill above the quarry, offering captivating views of Yr Wyddfa (Snowdon) and the Llŷn Peninsula. Ynys y Pandy, standing as a silent witness to Gorseddau’s hubris, serves as a poignant reminder of ambition and folly etched into the landscape of Snowdonia.
