Between Hexham and Haydon Bridge, the river Tyne runs through a wide green valley, and on the ridge to the north the line of Hadrian's Wall can be traced across fields and woods in a series of ditches, banks and stretches of masonry.
The man who saved much of this landscape was John Clayton, a nineteenth-century lawyer from Newcastle who bought several farms along the Wall to stop the stones being carried away for walls and barns. His house at Chesters stands beside the fort, and his collection of Roman finds is on display in the museum. Chesters is the best preserved fort for cavalry, with the bath house on the riverbank still standing to shoulder height, and a visit gives a good picture of life in a garrison. Alongside the Wall runs the Vallum, the great ditch to the south, and between the two you can walk over the field and feel the scale of the scheme.
Hexham itself has a fine abbey, built in the twelfth century on the site of a church founded in 674 by Saint Wilfrid, and its crypt, made of Roman stone from the old fort at Corbridge, survives from that time. The town has a market, an old gaol and a pleasant mix of shops and cafes. The ride on your map also leads to Durham, whose cathedral stands above the river Wear, and it is worth the trip if time allows.
The riding in the Tyne valley is mostly pleasant. The A69 is fast and busy, while the old road along the Wall, the B6318, is narrower and more scenic, with dips, farm entrances and sudden changes in the surface. Lanes on the south side of the river, through villages like Acomb and Haydon Bridge, are quieter and have good views. In winter, ice lingers in shaded dips, and in summer the road can be crowded with walkers and cars.
Hexham has eleven thousand people and is the place to refuel and eat, with a decent choice of pubs and tea-rooms. Haydon Bridge, a smaller village on the South Tyne, has a few shops and a good bakery. The best season for a visit is early autumn, when the light is clear and the bracken turns copper.