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.
England–Wales border then runs westwards to the River Teme, and follows the river southeastwards through Knighton before turning south towards the River Lugg at Presteigne, which is within Wales. The boundary continues southwards across hills to the River Wye, and follows the river upstream for a short distance to Hay-on-Wye, on the Welsh side of the border. It continues southwards and rises through and across the Black Mountains, following the Hatterall Ridge past Llanthony on the Welsh side and Longtown on the English side, to reach the River Monnow near Pandy. It then generally follows the river, past Pontrilas (in England) and