River Twiss
{{Short description|River in North Yorkshire, England}}
{{Use British English|date=July 2019}}
{{Use dmy dates|date=July 2019}}
{{Infobox river
| name = River Twiss
| image = River Twiss and Ingleton Viaduct - geograph.org.uk - 882495.jpg
| image_caption = River Twiss and Ingleton Viaduct
| source1_location = Kingsdale Beck, Keld Head
| source1_coordinates= {{coord|54|11|3|N|2|28|4|W|name=Source of River Twiss}}
| mouth_location = River Doe
| mouth_coordinates = {{coord|54|9|11|N|2|28|15|W|name=Mouth of River Twiss|display=inline,title}}
| subdivision_type1 = Country
| subdivision_name1 = England
| length_km = 4.17
| source1_elevation = {{convert|264|m|ft}}
| mouth_elevation = {{convert|118|m|ft}}
| basin_size =
}}
The River Twiss is a river in the county of Yorkshire, England. The source of the river is Kingsdale Beck, which rises at Kingsdale Head at the confluence of Back Gill and Long Gill in the Yorkshire Dales. Beneath Keld Head, the river changes its name to the River Twiss. It has two notable waterfalls, Thornton Force and Pecca Falls, and its course follows part of the Ingleton Waterfalls Walk,{{cite web|url=http://www.ingleton.co.uk/_scripts/activ-external.asp?url=www.ingletonwaterfallswalk.co.uk/|title=Ingleton Waterfalls Walk|accessdate=20 August 2011|url-status=dead|archiveurl=https://web.archive.org/web/20111002072947/http://www.ingleton.co.uk/_scripts/activ-external.asp?url=www.ingletonwaterfallswalk.co.uk%2F|archivedate=2 October 2011}} then through Swilla Glen to Thornton in Lonsdale and down to Ingleton, where it meets the River Doe to form the River Greta.
The English landscape artist J. M. W. Turner was a frequent visitor to the area, and his sketch of Thornton Force in 1816 is currently part of the Tate collection.{{cite web|url=http://www.tate.org.uk/servlet/ViewWork?cgroupid=65789&workid=38818&searchid=24129&roomid=false&tabview=image&imageid=229282|title=Landscape|accessdate=20 August 2011}}
Course
From the caves below Keld Head, water flows and combines with Kingsdale Beck to form the River Twiss. It flows south over Thornton Force and Pecca Falls and through woodland to join the River Doe at Ingleton.{{cite web|url=http://www.yorkshiredales.org.uk/lca_craven-dales.pdf|title=River course|accessdate=20 August 2011|url-status=dead|archiveurl=https://web.archive.org/web/20110929161337/http://www.yorkshiredales.org.uk/lca_craven-dales.pdf|archivedate=29 September 2011}}
=Waterfalls=
The drop of Thornton Force is about {{convert|14|m|ft}}. Pecca Falls has three drops totalling {{convert|30|m|ft}} that fall into their own deep pools.{{cite web| url=http://www.walkingenglishman.com/dalesguide/waterfalls/master.htm| title=Waterfalls| accessdate=20 August 2011| url-status=dead| archiveurl=https://web.archive.org/web/20130709070504/http://www.walkingenglishman.com/dalesguide/waterfalls/master.htm| archivedate=9 July 2013}}
Geology
In its upper part, the river flows through a valley carved into horizontal beds of Carboniferous Great Scar limestone. At Thornton Force, it crosses a notable unconformity into the underlying, steeply inclined Ordovician greywackes. The unconformity is clearly visible in the face of the waterfall. The Ordovician strata influence the character of the steep and narrow Swilla Glen and its waterfalls until, just north of Ingleton, the river crosses the Craven Fault and onto Carboniferous Limestone once again.
Crossings
- Ravenray Bridge (foot)
- Pecca Bridge (foot)
- Manor Bridge (foot)
- Unnamed Road, Ingleton
Gallery
{{Gallery
| title = River Twiss Images
| width = 180
| height = 140
|File:River Twiss - geograph.org.uk - 1125811.jpg|River Twiss, Raven Ray footbridge. To the north the limestone slopes of Keld Head Scars rise to the summit of Gragareth
|File:The River Twiss - geograph.org.uk - 519068.jpg|Manor Bridge over River Twiss
|File:River Twiss Ingleton - geograph.org.uk - 1125797.jpg|Cuckoo Island in the River Twiss
|File:River Twiss at Ingleton - geograph.org.uk - 882494.jpg|River Twiss seen from the road bridge in Ingleton
|File:Pecca Falls, River Twiss, near Ingleton - geograph.org.uk - 1469343.jpg|Pecca Falls, River Twiss, near Ingleton
|File:Thornton Force, River Twiss, Ingleton - geograph.org.uk - 830353.jpg|Thornton Force, River Twiss, Ingleton
}}
Sources
Ordnance Survey Open Data https://www.ordnancesurvey.co.uk/business-government/tools-support/open-data-support
References
{{reflist}}
{{Rivers of Yorkshire}}
{{authority control}}
{{DEFAULTSORT:Twiss}}