I rode around through Flintshire and Denbighshire to get to Snowdonia from Chester, last year. My recollection is that the lanes range from mildly undulating to hilly. Not that flat, unless you take the really busy roads like the A5.
The quiet roads in that area are very pretty. Just keep your wits about you. That part of Wales is not geared towards tourism like the areas from Betws y Coed onwards, so the lanes you want are not always sign-posted. And if you have to ask directions it helps to know a bit of Welsh !
Your friend could take the B road that runs through the Vale of Clwyd and just down to the east of Ruthin. Then cut down another B road towards Ruabon (near Wrexham).
If he is feeling energetic he could just head south through the lanes and cut through Clocaenog forest, then take the little roads that are parallel to the A5, going through Corwen and Llangollen. A bit lumpy in places but it's really beautiful and wild.
There are probably people who can fill in a bit on the Shropshire section. I'm not too sure about that. There are flat roads though, cos the bike course on the Shropshire triathlon is not hilly.
Maria
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