You’ll find it in the Wash, with the rest of the fortune that the then-King lost.

I think Edgar, if memory serves me correct, and I assume your talking about King John, crossing the Wash from Wisbeach,that a Gold coin, of his reign was found on a sandbar in the Wash by a boat fishing for, (Dredging) for cockles,

Personaly, looking at Ye Olde maps, his route would have been overland at the time, with only a small bit of the Wash to cross. There was one particular day, many yrs ago when there was a particularly low tide, that somewhere where the two old lighthouses are, a man actualy walked across the river.So it may well be more than a fairy tale.

Jim.

Lincoln .7