Type 'easy' or 'hard' to begin the quiz. Easy is a 1-degree range, hard is a 0.5-degree range. Then, name any 10K+ Europe city in each longitude range which fits the category label for each square.
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 250-500K) 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 range.
Quiz Takers 
I think that Saint Petersburg shouldn’t be on here (since it’s 15 letters). And in the “50 hardest” West Bromwich is listed twice
for ‘Saint’ i went with ‘St’ for countries where that is the typical spelling (via the country’s census/Wikipedia/other references to the city) – so for US/Russia and a few others it is ‘St’ whereas French/etc it is ‘Saint’ and other countries may be something like ‘Sankt’.
okay, though I’m pretty sure St. is not a typical spelling in Russia (since Russian doesn’t even have a St. abbreviation)
How long are you going to continue with this series?
If the US series is anything to go by, 14 letters… then a Long Names one for everything beyond that.
yeah long names coming soon for the balance, maybe one more 13-letter one.