Windmills had an important secondary function in many communities - they were used to send messages. The position of the sails on a windmill was used to convey news such as a death in the family, a wedding, or even a call to come to the mill as quickly as possible. Sail signals also warned of impending Nazi raids during World War II.

10 things you didn't know about #windmills

https://topicaltens.blogspot.com/2016/05/10th-may-windmill-day.html

#WindmillDay #WindmillWednesday