When:
April 7, 2017 all-day
2017-04-07T00:00:00-06:00
2017-04-08T00:00:00-06:00
Where:
http://www.sciencemadesimple.com/metric_system.html
On 7 April 1795, the metric system was adopted in France, where it had been developed.
Image courtesy of Pixabay.com