A466 road about long and runs through the counties of Herefordshire and Gloucestershire in England, and Monmouthshire in Wales. It runs south from Kingsthorne, on the A49 south east of Hereford to Monmouth, crossing the A40. After crossing the River Wye at the Wye Bridge, Monmouth and Bigsweir Bridge near Llandogo, it follows a picturesque route south down the Wye valley through Tintern and Chepstow to the M48 motorway at junction 2. The road crosses the border between England and Wales at three places along its length: at Buckholt, Redbrook, and Bigsweir. It runs through an Area of Outstanding Natural Beauty, and
Upper Wye Gorge fritillary and the white admiral. Upper Wye Gorge Upper Wye Gorge is a Site of Special Scientific Interest (SSSI), noted for its biological and geological characteristics, around Symonds Yat in the Upper Wye Valley on the Wales–England border. The site is listed in the 'Forest of Dean Local Plan Review' as a Key Wildlife Site (KWS). The SSSI, of which are in England and are in Wales, notified in 1969, is located north east of the town of Monmouth. It lies within the civil parishes of Goodrich and Whitchurch in Herefordshire, English Bicknor in Gloucestershire and within the community of