The River Cober is a short river in west Cornwall, England, United Kingdom. The river runs to the west of Helston into The Loe, Cornwall's largest natural lake.

The Loe, also known as Loe Pool, is the largest natural freshwater lake in Cornwall, United Kingdom. The earliest recorded appearance of this simple name form was in 1337, when it was called "La Loo", but is mentioned as 'the lake' in 1302; Situated between Porthleven and Gunwalloe and downstream of Helston, it is separated from Mount's Bay by the shingle bank of Loe Bar. Both the Loe and Loe Bar are situated within the Penrose Estate, which is administered by the National Trust, and are designated as a Site of Special Scientific Interest by Natural England. It is within the Cornwall Area of Outstanding Natural Beauty and is considered a classic Geological Conservation Review Site. The South West Coast Path, which follows the coast of south-west England from Somerset to Dorset passes over Loe Bar.