We'd been to the canal museum before, of course, but there was, I discovered, an exhibition about the use of canals on the Western Front, which is what we mainly went to see, as it finished that day.
It was a fascinating exhibition; the Canal du Nord hadn't yet been finished, and it was used as a highway for troops. The allies, as well as the enemy, made use of the canals, to bring food to a starving Belgium, and to move men and matériel. And there were hospital barges, and all sorts. The Royal Engineers played a huge, huge part in keeping the canals going - or sabotaging them, where necessary - and building temporary bridges where these had been destroyed and so on. There was even a secret port built, called Richborough, near Sandwich in Kent, from which barges could be sent across the Channel.
We saw the rest of the museum fairly briefly, and then went to explore the new King's Cross station, pausing for the obligatory shot of Platform 9 3/4: