Typical of the cuts which drain the Lincolnshire Fens is Counter Drain, running in a dead straight line. It looks almost navigable, doesn't it? But the map will tell you that it starts as a ditch near Market Deeping, other ditches run into it, there are lots of sharp bends and bridges, presumably low ones. And there's an obstruction at water level by the flood doors.
Below is a poor photo of Vernatt's Drain at Pode Hole. This joins the tidal Welland at Surfleet Seas End, the other side of Spalding; the Welland runs into The Wash, The OS map doesn't indicate the nature of the junction at SSE, whether there's a set of flood doors so that the drain can drain into the Welland at low tide. These things are best discovered on the ground!
Walkies again - This weekend my Ramblers group offered another suitable walk - actually on the short side, at six miles, but with some interesting terrain (and lots of mud...
13 hours ago