Y Garn to Carnedd y Filiast
Key: Mountain over 914m Peak over 600m Peak under 600m
Length: 10km Height gain: 840m Highest point: 947m Approx time: 5 hours gpx file
An interesting route covering the Northern end of the Glyderau. Starting from Llyn Ogwen, it is possible to return to the starting point, however this will involve a walk along the old A5. The ground covered is similar to that in y Glyderau from Llyn Idwal in ascent. The walk along the ridge is straight forward, however the descent suggested is very steep and covered in heather, thus a great deal of care needs to be taken. Views are across to the Snowdon Range, the Carneddau and also to Anglesey.
Follow the path suggested in y Glyderau from Llyn Idwal as far as Llyn y Cwn. Here however we leave the previous route, and take the path up the mountain to the right. This is Y Garn. There are two possible paths to follow. The most direct goes straight up the mountain, whilst the alternative goes off to the right slightly and takes you around the cliffs of Cwm Clyd.
An alternative route up Y Garn is to avoid the Devils Kitchen, and instead ascend the NE ridge (shown in the GPX file and on the map above). Shortly after leaving Idwal cottage take a path to the right which leads through a cut out section of rock. This will eventually reach Llyn Idwal, but further round than the path to the Devils Kitchen. Follow the route around to the right away from the lake and head up the fairly prominent ridge which leads to two small lakes, the larger of which is Llyn Clyd. Now continue the ascent till you hit the main ridge from Y Garn to Foel Goch, and turn left continuing for a short distance to the summit of Y Garn.
From Y Garn the views are across to Snowdon to the South West, and the Carneddau opposite. The rest of the walk stretches out in front and to the North West Elidir Fawr can be seen. This is known as "Electric Mountain", since the Dinorwig power station is housed inside. This is run by First Hydro Company, and is used to supply electricity at times of high demand. It is pumped storage, meaning that water is pumped up to an upper lake (Marchlyn Mawr) using off peak electricity, and when there is high demand this is dropped through the mountain turning turbines, and ends in a lower lake (Llyn Peris). We will be passing Marchlyn Mawr later in the walk.
Head off North from Y Garn, descending at first, and then reaching a flatter section of ground. There are two options here. Either cross the ladder style to your right and follow the grassy slope up to Foel Goch or take the path slightly to the left which will skirt the summit. The route up to Foel Goch is straight forward. Take a few moments to look across to Tryfan (translation as three stones) before taking a steep descent to your left. This is down some steep loose ground where you will join the route which skirts the summit. If you find it necessary there is a cut off from here. Just at the bottom of the slope is a ladder style which leads down steep ground into the Nant Ffrancon valley.
Assuming you are continuing you will see a well defined path which goes round to Elidir Fawr. Follow this for a short distance and then when it turns off to the left continue straight up a steep grass slope to the summit of Mynydd Perfedd. This is a steep slope, but is not too long. When you reach the top continue straight along to Carnedd y Filiast. The upper reservoir (Marchlyn Mawr) can just be seen in a dip to the left. The route to Carnedd y Filiast is fairly flat and covers mixed ground.
The descent from Carnedd y Filiast is steep, and over heather, thus care needs to be taken. Also there are steep cliffs to the right which should be avoided. From the summit you should head off to the North-East. and head down over some moderate ground to where you will begin to drop steeply. The best advice here is to pick your own route whilst avoiding the cliffs to your right. Looking back you will be able to see the famous Atlantic Slab. About half way down you will see a stone wall to your right. You should try to head for this and then follow it down to the old A5.
If you have transport at both ends, or are using busses then it is just a short walk to Bethesda. If you need to get back to Ogwen Cottage turn right and walk for 3.75 km along the old A5.