Did a nice walk from Cambridge to Ely along the river cam / Ouse towpath. lots of wildlife on the way, mostly birds - grebes, cormorants, herons even spotted a Marsh Harrier (I think!).
Beautiful Fenland country from Cambridge to Ely (15+ miles) starting at The Green Dragon Pub in Chesterton Cambridge taking you to the centre of Ely.
You follow the towpath (on the left of the river) all the way up with the option to cross at a number of locks on the way.
It was cold and the trees are pretty sparse in the fens, but it was well worth braving the January air for!