Riding from Wylam, you’re probably best off heading to the south of Prudhoe, maybe over towards Chopwell. there’s a bit on the north side of the valley, but its mainly fields and farm tracks.
GrahamS of this forum lives in Wylam, he’ll know of trails more local.
If you fancy spinning/driving up the valley though, it starts to get interesting once you’re past Stocksfield. Prospect Hill and Dipton woods south of Corbridge has some fun trails, Dukeshouse/Cock Woods south of Hexham is my local, and there’s loads of singletrack in there.
Or head further south to the Shire for big country moorland epics.
If you need a guide, there’s a few of us ride from Hexham at 8pm every wednesday, meet by the Natwest. Email in my profile.
There’s also the Tyne Valley MTB club, of which I’m a member, who have regular rides, its worth getting on their email list as Ted who runs it does a lot of work on local trail development.