About a mile south from the A30, this glassy expanse of water has many myths and legends associated with it – including one that claims it's where Arthur was given his famous sword, Excalibur, by the Lady of the Lake. It's also supposedly bottomless: another local legend concerns young Jan Tregeagle, who made a pact with the devil and in return was damned to spend his days emptying the neverending pool with a leaking limpet shell.
It's generally too cold for swimming, and since there are no trees around its edges, it can be fiercely windy – but it's a mysterious and atmospheric place nonetheless.
To the west is Colliford Lake, Cornwall's largest and highest reservoir.