Pennines Pennines The Pennines , also known as the Pennine Chain or Pennine Hills, are a range of mountains and hills in England separating North West England from Yorkshire and North East England. Often described as the "backbone of England", the Pennine Hills form a more-or-less continuous range stretching northwards from the Peak District in the northern Midlands, through the South Pennines, Yorkshire Dales and North Pennines up to the Tyne Gap, which separates the range from the Cheviot Hills. Some definitions of the Pennines also include the Cheviot Hills while excluding the southern Peak District. South of the Aire Gap
Mountain range strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to the east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive,