The upper part of the valley is in the Cambrian Mountains and is enclosed by hills as it descends through Rhayader, Builth Wells and Hay-on-Wye before reaching the England-Wales border and becoming a broader vale through Hereford.
The lower part of the valley meanders past Ross-on-Wye and Monmouth, where it becomes the England-Wales border, before reaching the Severn Estuary at Chepstow.
Much of this section features limestone gorge scenery and dense native woodlands, which made the Wye Valley historically important as one of the birthplaces of the modern tourism industry.
The varied landscapes of the Wye Valley can be explained by underlying rocks and structures, and how ice and then the river and tributary streams have acted upon them through time.
The Lower Wye landscape was formed by the river acting on a series of layers of rock that dip towards the Forest of Dean.
The Wye Valley is important for its rich wildlife habitats including ancient gorge woodland, saltmarsh and limestone cliffs.
Caves near Symonds Yat and Chepstow provide evidence of settlement dating from Palaeolithic times, and finds from later Stone Ages such as the Neolithic have also been found.
Later, Iron Age forts along the lower Wye Valley, and in the Woolhope area, took advantage of the natural hilltops and promontories to form well-defended settlements.
Iron has been made in the Wye Valley since Roman times, using the ready supply of timber, good quality ore and abundant charcoal from the Forest of Dean.
The river provided transport for the raw materials and finished product, and with the introduction of the blast furnace in the 16th century, its tributaries began to be used for water power.
The valley woodlands were carefully managed to produce mature trees for shipbuilding, or by coppicing for charcoal, and to provide bark for tanning.
By 1727 shallow draught boats could get upstream beyond Hereford, and a significant shipbuilding industry developed at Monmouth, Llandogo, Brockweir and Chepstow.
However, by 1835 it was stated that the Wye "can scarcely be considered a commercial highway" above Monmouth, and by the 1880s Brockweir bridge was the effective upper limit of navigation.
As the 19th century progressed, the valley's industries gradually declined, and management of the woodlands lessened when there was no longer a ready market for their products.
The earliest known appreciation of the area's spectacular beauty can be dated to the beginning of the century, when John Kyrle developed the 'Prospect' at Ross-on-Wye, and it was later mentioned in verse by Alexander Pope.
The area became more widely known following the publication of works by the poet Thomas Gray, and, in particular, Observations on the River Wye by the Reverend William Gilpin, published in 1782.
Some of the most famous poets, writers and artists of the day made the pilgrimage to the great sights of Goodrich, Tintern and Chepstow – among them Coleridge, Thackeray and Turner.
[11] The first of Britain's great landscapes to be 'discovered', the Wye Valley's particular attraction was its river scenery, and the many guidebooks, engravings and paintings ensured a continuing steady stream of visitors.
A Management Plan for the AONB enlists a range of partners in conserving and enhancing its beauty for the benefit of present and future generations.