London was by far the largest urban agglomeration in the United Kingdom in 2025, with an estimated population of *** million people, more than three times as large as Manchester, the UK’s second-biggest urban agglomeration. The agglomerations of Birmingham and Leeds / Bradford had the third and fourth-largest populations, respectively, while the biggest city in Scotland, Glasgow, was the fifth largest. Largest cities in Europe Two cities in Europe had larger urban areas than London, with Istanbul having a population of around **** million and the Russian capital Moscow having a population of over **** million. The city of Paris, located just over 200 miles away from London, was the second-largest city in Europe, with a population of more than **** million people. Paris was followed by London in terms of population size, and then by the Spanish cities of Madrid and Barcelona, at *** million and *** million people, respectively. The Italian capital, Rome, was the next largest city at *** million, followed by Berlin at *** million. London’s population growth Throughout the 1980s, the population of London fluctuated from a high of **** million people in 1981 to a low of **** million inhabitants in 1988. During the 1990s, the population of London increased once again, growing from ****million at the start of the decade to **** million by 1999. London's population has continued to grow since the turn of the century, and despite declining between 2019 and 2021, it reached *** million people in 2023 and is forecast to reach almost *** million by 2047.

National and subnational mid-year population estimates for the UK and its constituent countries by administrative area, age and sex (including components of population change, median age and population density).

United Kingdom UK: Population in Largest City: as % of Urban Population data was reported at 19.234 % in 2017. This records an increase from the previous number of 19.203 % for 2016. United Kingdom UK: Population in Largest City: as % of Urban Population data is updated yearly, averaging 18.336 % from Dec 1960 (Median) to 2017, with 58 observations. The data reached an all-time high of 19.939 % in 1960 and a record low of 17.256 % in 1973. United Kingdom UK: Population in Largest City: as % of Urban Population data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s UK – Table UK.World Bank: Population and Urbanization Statistics. Population in largest city is the percentage of a country's urban population living in that country's largest metropolitan area.; ; United Nations, World Urbanization Prospects.; Weighted Average;

In 2025, Moscow was the largest city in Europe with an estimated urban agglomeration of 12.74 million people. The French capital, Paris, was the second largest city in 2025 at 11.35 million, followed by the capitals of the United Kingdom and Spain, with London at 9.84 million and Madrid at 6.81 million people. Istanbul, which would otherwise be the largest city in Europe in 2025, is excluded as it is only partially in Europe, with a sizeable part of its population living in Asia. Europe’s population is almost 750 million Since 1950, the population of Europe has increased by approximately 200 million people, increasing from 550 million to 750 million in these seventy years. Before the turn of the millennium, Europe was the second-most populated continent, before it was overtaken by Africa, which saw its population increase from 228 million in 1950 to 817 million by 2000. Asia has consistently had the largest population of the world’s continents and was estimated to have a population of 4.6 billion. Europe’s largest countries Including its territory in Asia, Russia is by far the largest country in the world, with a territory of around 17 million square kilometers, almost double that of the next largest country, Canada. Within Europe, Russia also has the continent's largest population at 145 million, followed by Germany at 83 million and the United Kingdom at almost 68 million. By contrast, Europe is also home to various micro-states such as San Marino, which has a population of just 30 thousand.

According to the 2021 Census, London was the most ethnically diverse region in England and Wales – 63.2% of residents identified with an ethnic minority group.

There were 514 settlements in Scotland in mid-2020. This is 5 fewer than in 2016, due to some settlements merging or falling below the threshold of 500 people. The population living in settlements and localities was 4,974,670. The population living outside settlements was 491,330. 91% of Scotland’s population lived in settlements and localities, which accounted for 2.3% of Scotland’s total land area. The largest settlement in Scotland was Greater Glasgow with a population of 1,028,220. Nearly 1 in 5 people living in Scotland in mid-2020 lived in Greater Glasgow. Almost all of Glasgow City’s and Dundee City’s population lived in a settlement (99.8% in both). In contrast, less than a third of Na h-Eileanan Siar’s population lived in a settlement (29.4%).

Chlamydia trachomatis is the most common sexually transmitted infection (STI) in England. Our objective was to perform a detailed survey of the molecular epidemiology of C. trachomatis in the population of Southampton UK attending the genitourinary medicine clinic (GUM) to seek evidence of sexual network activity. Our hypothesis was that certain genotypes can be associated with specific demographic determinants. 380 positive samples were collected from 375 C. trachomatis positive GUM attendees out of the 3118 who consented to be part of the survey. 302 of the positive samples were fully genotyped. All six of the predominant genotypes possessed ompA locus type E. One ward of Southampton known to contain a large proportion of students had a different profile of genotypes compared to other areas of the city. Some genotypes appeared embedded in the city population whilst others appeared transient. Predominant circulating genotypes remain stable within a city population whereas others are sporadic. Sexual networks could be inferred but not conclusively identified using the data from this survey.