Just south of Lake Gunn on the road to Milford Sound is Cascade Creek. This small but extremely clear river feeds into the Eglinton River. Either side there are large fields of wild lupins, as you can see on the opposite bank of the creek. The water is so fresh that I filled up my water bottle and drank it straight. It tasted the same as if I was swigging from a bottle of mineral water just out of the fridge.