Even though the mills at Kinderdijk were replaced by steam-powered, then diesel and electric water pumps, they are still kept in good working order and can be put into action any time, either for show or in case of power failure.
This was exactly the case during WWII when diesel shortages forced locals to return to wind power to keep their feet dry.
Today the sails can sometimes be seen turning on national and regional Mills Days (Molendagen).

As we finished our tour of the windmills we could begin to see a bit of clearing in the sky.
We returned to our ship and had a delicious hot lunch.
The people who took the electric bike tour or the walking tour were all bemoaning how miserable it was out there.
We tried not to brag about how comfortable our visit was in the little barge.
The weather cleared as we headed up the Rhine towards Cologne.
We enjoyed an afternoon of sitting in the sun on our own private deck watching the scenery as we cruised along.