The Mendip Hills is a range of limestone hills to the south of Bristol and Bath in Somerset, England. Running from Weston-super-Mare and the Bristol Channel in the west to the Frome valley in the east, the hills overlook the Somerset Levels to the south and the Chew Valley and other tributaries of the Avon to the north. The hills give their name to the local government district of Mendip, which administers most of the area. The higher, western part of the hills, covering 198 km² has been designated an Area of Outstanding Natural Beauty, which gives it a level of protection comparable to a national park.
The hills are largely formed from Carboniferous Limestone, which is quarried at several sites. ash–maple woodland, calcareous grassland and mesotrophic grassland which can be found across the Mendip Hills provide nationally important semi-natural habitats. With their temperate climate these support a range of flora and fauna including birds, butterflies and small mammals. The dry stone walls that divide the pasture into fields are of botanical importance as they support important populations of the nationally scarce wall whitlowgrass.