Metropolitan Area

A metropolitan area, sometimes referred to as a metropolitan region, metro area or just metro, is a region consisting of a densely populated urban core and its less-populated surrounding territories, sharing: industry, infrastructure, and housing.[1] A metro area usually comprises multiple jurisdictions and municipalities: neighborhoods, townships, cities, exurbs, counties, districts, states, and even nations like the eurodistricts. As social, economic and political institutions have changed, metropolitan areas have become key economic and political regions.[2] Metropolitan areas include one or more urban areas, as well as satellite cities, towns and intervening rural areas that are socio-economically tied to the urban core, typically measured by commuting patterns.[3] https://en.wikipedia.org/wiki/Metropolitan_area

aka City Region

in the US these are really called Metropolitan Statistical Area-s or MSA-s. https://en.wikipedia.org/wiki/Metropolitan_statistical_area

list of all 381 https://en.wikipedia.org/wiki/List_of_Metropolitan_Statistical_Areas

• largest is NYC-area with 20M people at a Population Density of just 1,876/sqmi
• 2: Los Angeles 12M ppl, Population Density 2,645.0/sqmi
• 3: Chicago 9.5M ppl, 1,318/sqmi
• 11: San Francisco 4.5M ppl, 1,825/sqmi
• 15: Seattle Wa 3.7M ppl, 596/sqmi
• 34: San Jose/Sunny Vale/Santa Clara 2.0M ppl, 742/sqmi
• top 53 each have over 1M people
• San Francisco/Silicon Valley area is made up of multiple MSA-s within 1 CSA (Combined Statistical Area: overall 8.6M ppl at 806/sqmi https://en.wikipedia.org/wiki/San_Jose-San_Francisco-Oakland,_CA_Combined_Statistical_Area
• smallest is 54k people
  • note this isn't consistent with link at City Size page