Just before it reaches the sea, the River South Esk flows through Montrose Basin, a wide, shallow bowl that empties and fills twice a day with the tide. It’s the largest stretch of inland salt water in Britain. Low tide exposes a huge expanse of mud flats and salt marsh, rich in tiny shellfish and worms that make a rich feeding ground for birds.
The basin is managed as a Local Nature Reserve. The Scottish Wildlife Trust run a visitor centre where telescopes and video cameras will get you up close to the birds, and you can find out more about this fascinating place.