Type 'easy' or 'hard' to begin the quiz. Easy is a 5-degree grid, hard is a 2.5-degree grid. Then, try to name the LARGEST European city in each grid square which fits the category label for each square. To name a city, you must first click on the grid square to make it have a GREEN border. Then, type in the city answer for that square followed by a '.' (a period). You are given a score from 0 to 100 based on your answer's population compared to the largest city accepted in that square (100 being you named the largest city).
LETTER: means the city starts with that letter.
NUMBER RANGE: (such as 2-5, 10+) means the city contains that many letters (excluding spaces and special characters).
POPULATION RANGE: (such as 50-100K) means the city has that range for its population.
2+ WORDS means the city name has 2 or more words (words denoted by a space or hyphen).
At the end of the quiz the largest population missed answer will show in each unanswered square, and for those answered the largest city will be listed if you didn't answer it.
Quiz Takers 
With the recent number of cities, it is impossible to get a high score on the beginner level (9899 cities vs 9901 cities previously).
Yes it is constantly being updated as city-population.de updates – so soon it should be back above 9899.
When you’re back on the site, it’s currently impossible to get a high score, because the top scorers have 9468 cities and only 9462 are currently available.
I’m almost sure the previous version of the quiz (and the longitude one too) had a countries remaining counter which failed to be included in these updated versions. I think that counter is more or less a giving on coverage quizzes. It’s especially useful on higher levels where gaps are very small and I don’t have a clue on what countries I’m still missing. I think a 5/10 remaining countries would be enough.
Ah, the counter is there (though it reads States rather than Countries), but once we choose the level it’s gone so it’s all a matter of tweaking the quiz.