 bala lake (; , ) is a large lake in gwynedd, wales. it was the largest natural body of water in wales prior to the level being raised by thomas telford to help support the flow of the ellesmere canal. it is  long by  wide, and is subject to sudden and dangerous floods. the river dee runs through it and the waters of the lake are famously deep and clear. the town of bala sits at its northern end and the narrow gauge bala lake railway runs for several kilometres along the lake's southern shore. ==origins of name== george borrow wrote of the lake in wild wales in 1856, "the lake has certainly not its name, which signifies 'lake of beauty', for nothing". in english the lake is named after the nearby town of bala, whose name means "outlet of a lake" in welsh. an older, now unused, english name for the lake is pemble mere or pimble mere. (many variant spellings are recorded.) ==biology== bala lake has abundant pike, perch, brown trout, roach, eel. it also contains the endemic gwyniad, now listed as critically endagered by the iucn due to the introduction of the invasive and non native ruffe.- snowdonia guide, bala lake website it also contains the very rare mollusc myxas glutinosa â the glutinous snail. according to legend, whilst the dee itself flows through the lake, the waters never mix. however this was not confirmed by the detailed [[l
Bala,_Gwynedd Llangywer Llanuwchllyn Llanycil Ramsar_sites_in_Wales Reservoirs_in_Gwynedd Reservoirs_in_Snowdonia River_Dee_(Wales) River_regulation_in_Gwynedd River_regulation_in_Snowdonia Sites_of_Special_Scientific_Interest_in_East_Gwynedd Tourism_in_Gwynedd Tourism_in_Snowdonia