First choose any Europe 10K+ pop city by entering it and choosing it in the drop-down box. Then, name any Europe 10K+ city in each 100 km circle/ring as the rings expand outward from your city of choice, trying to name SECOND LARGEST city in each circle. The first circle will include your city of choice as a possible answer.
PLEASE NOTE - You must type a '.' (period) after each city to submit it to prevent answering another city with a name you would be have to type to get your answer. If multiple cities have the name you submitted, only the largest one will be counted.
You accumulate points based on the population of the city you named in relation to the second largest city in the circle. A smaller city’s point total will be the ratio of its population to the largest, so if you name a city of 75K people and the largest city has 100K, you get 75 points. Naming the largest city will get you points based on the ratio of the 2nd largest city's population to the largest city's.
When you run out of time or end the quiz, you will see the current ring’s 2nd largest city at right (under ‘Answer Stats’ by your coordinates).
For example, if you choose ‘Paris’ – you will be shown a circle of radius 100 km centered at Paris. Naming any city in this circle (including Paris) will cause another ‘ring’ of radius 100 km to appear outside that circle, however - you will want to try naming the SECOND LARGEST city you can to get more points. After completing that circle, you now need to name any 10K+ Europe city in the new ring (but not within any previous circles/rings), again trying to name the 2nd largest city. If there are not two cities within the next ring of that distance, the ring will keep expanding by that distance until two cities fall within it.
Quiz Takers 
This quiz is a bit wrong in the Rogaland section. I admit I had to look up the names for some areas after my quiz because I actually live in Rogaland, and I know a lot about this area geographically, but some places have simply the wrong names altogether, or the names have a more recognized version of it.
Stenebyen should also be ok with Tjelta which is the more common name for the place.
Østenstad should also be ok with Skjoldastraumen
Padlene should also be ok with Førland
Høie should also be ok with Stegaberg
Ydstebøhamn should also be ok with Kvitsøy
Nærland and Kolnes should be removed, because it’s a farming area, it’s not even a village, let alone a city.
With the exception for Ydstebøhamn being another name for Kvitsøy, when you ask people where they come from, they will always answer Kvitsøy. I have never heard anyone speak about Stenebyen, it has always been Tjelta. Those 3 remaining in Haugalandet (Østenstad, Padlene and Høie is names I never heard about (with the exception for the football player Egil Østenstad, but never heard about the location), but I know about the other names, I don’t know the reason why the secondary names of these places are more famous, maybe a local can explain that to me. They should be added as an acceptible option for the answers.
What I think might be the reason it is like that, let’s take Padlene/Førland as an example, where Padlene is kind of like the name of a neighborhood, while the school the major roads in the area is called Førland.
Østenstad/Skjoldastraumen have the same issue, while it seems Østenstad is a neighborhood in the area, major things in the area is called Skjoldastraumen (ex. Coop Prix Skjoldastraumen, Skjoldastraumen Camping, also having the mailing address being Skjoldastraumen).
And then you have the long version names of some locations.Hjelmelandsvågen could be simply Hjelmeland and Lyefjell could simply just be Lye
I’ve changed to add those alternatives. The place names are localities from the Norwegian census which are recorded on citypopulation.de.