Mud venues around Edinburgh, Midlothian and Borders

Hi, looking for recommendations for good muddy venues near to Edinburgh. For example, fields and walks, or rivers and streams with muddy pools.
Ideally secluded or hidden and away from public view.
blue450@hotmail.co.uk
Long shot, but here's hoping!

Ideally secluded or hidden and away from public view.
blue450@hotmail.co.uk
Long shot, but here's hoping!
