This really is a ride of two halves. From Abergavenny to Brecon, it’s a gentle towpath amble along the lovely Monmouthshire & Brecon. After Brecon… let’s just say it’s a bit less gentle. You wouldn’t expect a route called “Cycle across the Beacons” to be flat, and it isn’t. Indeed, although Sustrans worked with the Brecon Beacons National Park to set it up, the hilly section isn’t numbered as part of the National Cycle Network – they considered it too tough for that.