Herefordshire Worcestershire and Warwickshire" NUTS 2 region. The River Wye, which at is the fifth-longest in the United Kingdom, enters the county after briefly being its border with Powys. It flows through both Hereford and Ross-on-Wye before returning to Wales. Leominster is situated on the River Lugg, a tributary of the Wye. There are two Areas of Outstanding Natural Beauty in the county. The Wye Valley is located in the river's valleys south of Hereford, while the Malvern Hills are in the east of the county, along its border with Worcestershire. Herefordshire is one of the 39 historic counties of England.
River Wye river from Redbrook to Chepstow forms the border between England and Wales. The River Wye forms two Sites of Special Scientific Interest, one covering the Upper Wye ("Gwy Uchaf") above Hay-on-Wye, and one covering the Lower Wye ("Gwy Isaf") downstream to Chepstow. The criteria for inclusion of the river as an SSSI include geology, topography, flora, mammals, invertebrates, fish and birdlife, as the river and its tributaries constitute a large linear ecosystem. The Lower Wye SSSI is itself divided into seven units of assessment set by Natural England, and administrative responsibilities are shared between the county authorities of Powys, Herefordshire,