Most of the dales in the Yorkshire Dales are named after their river or stream (e.g. Arkengarthdale, formed by Arkle Beck).
Geographically, the classical Yorkshire Dales spread to the north from the market and spa towns of Settle, Deepdale near Dent, Skipton, Ilkley and Harrogate in North Yorkshire, with most of the larger southern dales (e.g. Ribblesdale, Malhamdale and Airedale, Wharfedale and Nidderdale) running roughly parallel from north to south. The more northerly dales (e.g. Wensleydale, Swaledale and Teesdale) running generally from west to east. There are also many other smaller or lesser known dales (e.g. Arkengarthdale, Barbondale, Bishopdale, Clapdale, Coverdale, Dentdale and Deepdale, Garsdale, Kingsdale, Littondale, Langstrothdale, Raydale, Waldendale and the Washburn Valley) whose tributary streams and rivers feed into the larger valleys.
The characteristic scenery of the Dales is green upland pastures separated by dry-stone walls and grazed by sheep and cattle. The dales themselves are 'U' and 'V' shaped valleys, which were enlarged and shaped by glaciers, mainly in the most recent, Devensian ice age. The underlying rock is principally Carboniferous limestone (which results in a number of areas of limestone pavement) in places interspersed with shale and sandstone and topped with Millstone Grit. However, to the north of the Dent fault, the hills are principally older Silurian and Ordovician rocks, which make up the Howgill Fells.