Oh no, the world map has been covered up with circles! To clear a circle you have to type a city inside it that is either: A) a world capital B) one of the 2 largest cities C) one of the 2 cities furthest from a larger city
Explanation of colours: Big circles: - blue indicates presence of capital cities - red indicates lack of cities
City circles: - red means it's not one of the largest - green means it's not one of the furthest from a larger city - blue means it's a capital city
So: - a white dot means it has all 3 colours, hence it indicates a capital city that is neither one of the largest or one of the furthest to a larger city inside its circle - a black dot means it as none of the 3 colours, hence it indicates a non-capital city that is both one of the largest and one of the furthest from a larger city in its circle.
Data for 1M cities from citypopulation.de, data for smaller cities from geonames.org
Cities with no more than 10,000 inhabitants are only considered if they have no larger city within 100 km