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 
Updated – as-of now Netherlands has 342 municipalities instead of 355 when I first made this quiz.
Maybe you could allow the Dutch names of Frisian municipalities.
If you have them let me know, I took what is on citypopulation.de
Wow, the municipalities of Friesland have really changed since when I knew them ten years ago.