Llyn Llyffant

{{Short description|Lake in Conwy County Borough, Wales}}

{{Use dmy dates|date=November 2019}}

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| name = Llyn Llyffant

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| location = near to Carnedd Llewelyn, Conwy County Borough, Wales

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Llyn Llyffant is the highest lake in Wales, (although in reality the size of a large pond), located at grid reference SH 687 645.{{cite web|url=https://www.geograph.org.uk/photo/910130 |title=Llyn Llyffant - the highest lake in Wales:: OS grid SH6864 |publisher=Geograph Britain and Ireland |date= |accessdate=2010-05-02}}

Its name translates into English as "frog lake". It lies at an elevation of approximately 815m above sea level.