Groningen is the capital city and main municipality of Groningen province in the Netherlands. It is the largest city in the north of the Netherlands. As of December 2021, it had 235,287 inhabitants. It has a land area of 168.93 km2 (65.22 sq mi), and a total area, including water, of 180.21 km2 (69.58 sq mi). Its population density is 1,367 residents per km2 (3,540 per square mile). On 1 January 2019, it was merged with the municipalities of Ten Boer and Haren. The Groningen-Assen metropolitan area has about half a million inhabitants. Groningen is a university city, and students comprise an estimated 25% of its total population. Groningen was established more than 950 years ago. Historically, it was a semi-independent city-state, a member of the Hanseatic League, and the dominant regional power in the north of the Netherlands.
Netherlands - Groningen 
Germany - Köln
United Kingdom - Londres
Thailand
Japan - Tokyo
Russia - Moscou