Home » Routes » Europe » Wales » Snowdonia National Park » The Moelwynion » Cwmorthin and Rhosydd Quarry from Tanygrisiau

Cwmorthin and Rhosydd Quarry from Tanygrisiau

By Dave Roberts   

on June 21, 2015    5/5 (1)

Cwmorthin and Rhosydd Quarry from Tanygrisiau

Further Details

Route Summary:

Route Start Location:

3.15 km 250 m

Calculate the time using Naismith’s Rule and factor in your own pace.

Activivity Type: Moderate Walk

Summits and Places on this Route


Check out the businesses nearby for more places to stay and drink.


Remember that we cannot outline every single hazard on a walk – it’s up to you to be safe and competent. Read up on Mountain Safety , Navigation and what equipment you’ll need.

Parking :

Public Transport:

Traveline for UK Public Transport

Recommended Maps

OS Explorer OL17 Snowdon & Conwy Valley, Snowdonia BMC (British Mountain Map) ,  Explorer OL18 Harlech, Porthmadog & Bala Map, Landranger 115 Snowdon & Caernarfon


Weather Forecast:

Met Office Snowdonia Mountain Weather

Check out our Best Mountain Weather Forecast?

Cwmorthin and Rhosydd Quarry from Tanygrisiau Ordnance Survey Map and GPX File Download

Download file for GPS

Cwmorthin and Rhosydd Quarry from Tanygrisiau

This short walk takes you through Cwmorthin and up to expolore the quarry at Bwlch Rhosydd and makes an ideal half day walk or even a trail/fell run. You can also walk to the far end of Cwmorthin for an easier option.

Remember that the distance below is just ONE WAY!

While it has been tagged as being in “Snowdonia” – not a single step of this walk is actually in the National Park (at present) but this is just the most convenient way to categorise the walk.

1 Start from Tanygrisiau (see right for travel details via Google), with a steep pull up the slate track into Cwmorthin.


2 At Llyn Cwmorthin, you can walk to the lake’s head to take in the view up Llyn Cwmorthin.


3 The track continues on the level for a couple of kilometres, past an old chapel and as far as Plas Cwmorthin, the former quarry manager’s house. Those after an easier route can turn back at this point.



4 The track pulls uphill for around 800m into Bwlch Rhosydd and climbs just over 100m, being easy to follow.


5 At Bwlch y Rhosydd, you’ll see the remains of the Rhosydd Quarry, though care needs to be taken here in mist that you can find the track back down!


6 Once you’ve had a breather and enough exploring, remembering that exploring any workings and entering any buildings is not recommended, retrace your steps.

Dave Roberts founded Walk Eryri in 2004, with the aim of providing routes that are off the beaten track. Walk Eryri is now part of Mud and Routes which continues to provide more off beat routes and walks in Snowdonia and beyond. Dave has been exploring the hills of Eryri for over thirty years, and is a qualified Mountain Leader. Dave also established Walk up Snowdon, Walk up Scafell Pike and Walk up Ben Nevis just to mention a few.
Share this – [Sassy_Social_Share]

Please rate this

More Posts By This Author

2 thoughts on “Cwmorthin and Rhosydd Quarry from Tanygrisiau”

  1. Nice report Dave. Rhosydd was our (myself and wife and kids) on our visit to Cwmorthin last month. Unfortunately, after the kids had had finished hopping and skipping around Llyn Cwmorthin they were too ‘chin strapped’ to make Rhosydd. We did climb up to the open chambers of the old Conglog mine though. Rhosydd scheduled two weeks from now.

  2. Hi Dave – nice report. This looks like a stunning walk. I’m a researcher on BBC Weatherman Walking and we’re interested in this route or a similar one where we can see the landmarks of the lake and the quarry that is relatively high… I’m wondering if you can help though; do you know who owns this land? Is it publicly owned or is it owned by the National Trust the quarry?
    Thank you in advance

Leave a Reply