The Howgill Fells are bounded by the River Lune, to the north by upper reaches of the River Lune, and to the east by the River Rawthey. The fells include two Marilyns: The Calf - and Yarlside - and a number of smaller peaks, including five Hewitts. Prior to 2017, a part of the Howgill Fells lay within the Yorkshire Dales National Park though the entire range has been included since then. They have been within the modern county of Cumbria since the county boundary changes in 1974. They were originally shared by the West Riding of Yorkshire and Westmorland.
Geology
Unlike the Carboniferous Limestone landscapes typical of much of the Yorkshire Dales and Orton Fells, the range is formed from lower Palaeozoic slates and gritstones. An inlier of Ashgill age rocks of the OrdovicianDent Group in the vicinity of Backside Beck in the east are the oldest rocks in the range whilst the oldest Silurian rocks are the laminated siltstones of the Llandovery age Stockdale Group. These are overlain by more than 250m thickness of dark grey mudstones and siltstones of the Brathay Formation which, with the overlying Coldwell and Wray Castle formations are collected together as the Tranearth Group and, in age terms, span the Wenlock / Ludlow boundary. The larger part of the range is formed from sandstones of the Coniston Group. This unit is roughly 1000m thick; it includes a basal Screes Gill Formation up to 300m thick and also contains numerous siltstone bands. These are overlain by the sandstones, mudstones and siltstones of the Bannisdale and Kirkby Moor formations, collected together as the Kendal Group. Structurally the bedrock is folded on a broad scale into a roughly east-west aligned Carlingill Anticline with the Castle Knotts Syncline to its south. Numerous smaller amplitude folds are developed on the limbs of these two folds. A series of normal faults aligned between N-S and NE-SW cut the range whilst its eastern and southeastern margin is defined by a combination of the Sedbergh, Rawthey and Dent faults. Quaternary deposits include widespread glacial till in the valleys and on lower ground generally. Though the range was covered by the British ice-sheet during successive glaciations, Cautley Crag is the only well-developed glacial cirque within the Howgill Fells. Post-glacialriver sands and gravels are found on the floor of river valleys, notably on the margins of the range. Peat is found on some hill spurs but is not widely developed whilst scree is found in places, notably around the Cautley Spout area. Debris cones of cobbles are found, notably in Langdale and Bowderdale. The Lune Gorge which defines the western edge of the Howgills is a major glacial meltwater channel.
