By Sue Viccars. Author: Sue Viccars. South Devon and Dartmoor Pathfinder Walking Guide Ordnance Survey Pathfinder 1 28 Outstanding Circular Walks Devon Nature Walks Adventure Pathfinder Guides. Title: South Devon and Dartmoor Pathfinder Walking Guide Ordnance Survey Pathfinder 1 28 Outstanding Circular Walks Devon Nature Walks Adventure Pathfinder Guides.