Leck Beck

{{Short description|River in Cumbria and Lancashire, England}}

{{Use dmy dates|date=April 2022}}

{{Infobox river

| name = Leck Beck

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| image = Leck Beck - geograph.org.uk - 600756.jpg

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| subdivision_type1 = Country

| subdivision_name1 = United Kingdom

| subdivision_type2 = Part

| subdivision_name2 = England

| subdivision_type3 = County

| subdivision_name3 = Lancashire, Cumbria

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| source1 = Crag Hill

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| mouth = Confluence with River Lune

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Leck Beck is a watercourse in Lancashire with its source on Crag Hill in Cumbria between Leck Fell and Casterton Fell.

For several kilometres near the start of its course, the water flows into the Ease Gill Cave System, part of The Three Counties System, the longest cave system in Britain (and 26th longest in the world) via 14 major sink holes, to resurge at a major spring at Leck Beck Head.{{cite web

|url=http://www.english-nature.org.uk/citation/citation_photo/1001420.pdf

|publisher=English Nature

|title=Leck Beck Head Catchment Area}}{{cite web|last1=Gulden|first1=Bob|title=World's Longest Caves|url=http://www.caverbob.com/wlong.htm|archive-url=https://web.archive.org/web/20060515145704/http://www.caverbob.com/wlong.htm|url-status=usurped|archive-date=15 May 2006|access-date=14 July 2015}}

The rising of Leck Beck Head {{gbmappingsmall|SD660 800}} was dived extensively in the 1980s and required underwater digging and the use of an air chisel to make progress.{{cite journal|title=Leck Beck Head opened up|year=1993|journal=Descent|number=110|pages=8}} The overflow for this rising, Witches Cave (Yorkshire), has been dived through a 300m sump into Witches II. A dry entrance was dug into Witches II from the surface in 2010.{{citation needed|date=November 2011}}

The Beck flows through Leck, Cowan Bridge and Overtown before joining the River Lune near Nether Burrow.