free to be able to rate and comment on reports (as well as access 1:25000 mapping).
A trip report from a couple of years back - I've just found the photos.
As well as their own attractions, these hills have great views of their more famous neighbours.
IMG_3730 by
Half Man Half Titanium, on Flickr
However, I would caution anyone who is a walker but not a scrambler. From the A5, the Carneddau look more friendly and approachable than the Glyderau. But on the standard Ogwen circuit around these hills, there are two scrambly sections - the rocky ridge about Ffynnon Lloer, which is easy and pleasant, and the descent from Craig yr Ysfa, where a short 45 degree slab has to be descended (with good holds). It's hardly Crib Goch - but it's not a stroll in the park either. I decided instead to descend the grassy southern slope of the Ysgolion Duon ridge to join up with my ascent route.
I think the ascent of the southern slopes of Pen yr Ole Wen is an extraordinarily beautiful walk. The path meanders up a grassy finger of land alongside two chattering streams. Waterfalls are everywhere, and the Carneddau wild horses were enjoying the sunshine.
IMG_4428 by
Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
The skyline in this photo is the scrambly bit.
IMG_4457 by
Half Man Half Titanium, on Flickr
After a while I had a glimpse of the hidden llyn, Ffynnon Lloer (= "spring/source of the moon") and the ridge steepens to the scrambly section. On the upper ridge you don't know where to look - on the left are the Glyderau, while on the right there are great views down to Ffynnon Lloer.
IMG_4493 by
Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
I didn't stop at the cairn, as there was a large party coming up the hill. I headed over to the south summit, a quiet hillwalker's Heaven, with flowers among the contorted rocks.
IMG_4609 by
Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
Arans on the skyline to the left of Tryfan's summit
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Half Man Half Titanium, on Flickr
Elidir Fawr and Carnedd y Filiast's huge crags, including the improbable Atlantic Slab, and Anglesey in the distance.
IMG_4763(1) by
Half Man Half Titanium, on Flickr
Ffynnon Lloer from the ridge to Carnedd Dafydd
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Half Man Half Titanium, on Flickr
The skyline is the Clwydian Hills and the Berwyn.
IMG_4726 by
Half Man Half Titanium, on Flickr
Snowdon from Carnedd Dafydd
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Half Man Half Titanium, on Flickr
Cwm Llafar and Ysgolion Duon from Carnedd Dafydd
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Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr
Nice things on the descent, which is pathless but a great route for anyone with knee problems.
IMG_4881 by
Half Man Half Titanium, on Flickr
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Half Man Half Titanium, on Flickr