Snowdonia Slate Quarry Circuit
Welsh slate miners' roads in Snowdon's brutal shadow
The Snowdonia Slate Quarry Circuit follows century-old mining roads carved into the flanks of Snowdon, connecting the massive slate quarries at Blaenau Ffestiniog with Llanberis Pass. These tracks were blasted from solid rock by Welsh miners hauling slate down to the narrow-gauge railways, with some sections still showing the original horse-drawn cart ruts. The route threads between Dinorwig’s terraced quarry faces and Penrhyn’s flooded pits, crossing exposed ridges where weather can turn deadly in minutes.
Expert difficulty demands serious preparation — conditions shift from clear to white-out fog without warning, and the exposed moorland offers zero shelter. Modified 4×4 essential with recovery gear, GPS, and emergency supplies. Avoid winter completely; even summer brings sudden storms. Permission required from Crown Estate for some sections. No services for 40 miles once you’re committed. This is about experiencing industrial Wales at its most raw and unforgiving.
Trail Specs
| Difficulty | Expert |
|---|---|
| Trail Type | Technical 4x4 |
| Surface | Rock |
| Features | High Altitude, Historic, Remote |
| Length (miles) | 34 mi / 55 km |
| Duration | 2 days |
| Max elevation (ft) | 3300 ft |
| Best season | July-September |
| Minimum vehicle | Modified 4WD with recovery gear |
| Nearest town | Llanberis, Gwynedd |
| Land manager | Snowdonia National Park Authority |
| Permit required | Yes |
| Cell service | None |
| Water crossings | No |
| Dispersed camping | No |
| Start coordinates | |
| End coordinates | |
| Copy both for Google Maps directionsClick to copy the directions URL · or open it directly in a new tab | |
| Find on Google | Search on Google → |
Location
Trail Conditions
No recent condition reports. Be the first to post one.
Log in to post a condition report.
Frequently asked questions
Can a lightly lifted Defender or 4Runner run this, or does it need serious modifications?
A lightly lifted stock Defender can attempt sections, but the rocky quarry tracks demand proper underbody protection, a locking differential, and at minimum an aftermarket suspension setup. A bone-stock vehicle will get damaged — exposed rock shelves and off-camber ledges will find your sills and transfer case.
Is the trail accessible outside of July–September?
Outside that window, Snowdonia's weather turns hostile fast — snow, ice, and saturated ground make the high-altitude sections genuinely dangerous and potentially impassable. The Snowdonia National Park Authority also restricts motorised access on certain tracks outside summer months, so check current conditions before even considering a shoulder-season run.
Do you need a permit, and where do you get one?
Yes, a permit is required through the Snowdonia National Park Authority. Contact them directly via their Gwynedd office — permits are not available at the trailhead, and running the route without one risks a fine and damages access rights for everyone.
What's the hardest section and what makes it genuinely dangerous?
The exposed quarry-access climbs above 3,000 feet are where the trail earns its expert rating — loose shale over solid rock, near-zero traction on wet surfaces, and sheer drop exposure with no guardrails. A mistake here isn't just a recovery situation; it can be a rollover with nowhere to go.
There's no cell service for 34 miles — what's the realistic comms and recovery plan out here?
A satellite communicator (Garmin inReach or SPOT) is non-negotiable on this circuit — emergency services in this part of Gwynedd will have no idea you're out there otherwise. Run with at least two capable vehicles, carry full recovery gear, and plan your overnight camp with the understanding that a helicopter callout on Snowdon is a serious, expensive undertaking.
Trail track
No GPX track for this trail yet. If you've driven it and have a track, contribute below.
Log in to contribute a GPX track.