Weardale is a dale, or valley, of the east side of the Pennines in County Durham, England. Large parts of Weardale fall within the North Pennines Area of Outstanding Natural Beauty (AONB) – the second largest AONB in England and Wales. The upper valley is surrounded by high fells (up to O.D. at Burnhope Seat) and heather grouse moors. The River Wear flows through Weardale before reaching Bishop Auckland and then Durham, meeting the sea at Sunderland. Running roughly parallel to Weardale to the south is Teesdale. To the local people of Weardale, the area represents a part of English heritage and culture that is seldom encountered outside the sheltered valleys of the north of England. Walkers visiting Slit Wood in Westgate at the right time of year encounter several rare flowers.