The object of this quiz is to adjust each circle's radius so it contains the target population shown at the right but ONLY within Europe. When you click Start you will be shown a marker on a random populated Europe grid square (there are over 90K 10x10 km grid squares used for the data, courtesy of https://human-settlement.emergency.copernicus.eu/index.php). Also you will see an adjustable circle of radius 100 km to start. Adjust the circle's radius by dragging it until it contains the target number of people shown - this target will be between 5 and 100 million people. Then click submit. You are scored on how close your circle's population is to the target.
PLEASE NOTE: ALL of Turkey is included in counting population (not just European portion), and the portion of Russia west of 61.5 degrees E (just east of Chelyabinsk). Nothing outside Europe (such as Africa or middle east other than Turkey) is included toward the population count within a circle.
Quiz Takers 
the quiz doesn’t seem to be accepting Neuenburg am Rhein as a city :/
It answers by just typing ‘Neuenburg’
I am afraid it does not do this…
Ah sorry, now it’s good. May have to refresh the quiz.
thanks!
was typing Bietigheim Bissingen and it took the first part & I thought what finally you no longer have to type the full name and then after I hit end quiz I see that I missed that exact city because supposedly there’s another town called Bietigheim and it took that one instead :/
hate when that happens