The capital city of the US & the capital city of Latvia are .. kinda different in order-of-magnitude..

Further, city-limits are kind of bogus, when metropolises tend to be sprawling ( try finding that actual-limit of Tokyo, as 1 extreme example ).

I believe the sanest way to discover the "size" of a city is simply to physically be in it, & then get to the contrasting-city, & be in that one..

I'm saying this as a person who used to live in a city generally known as Toronto, but which used to be multiple cities ( Scarborough, East York, Toronto ( proper ), etc, until it got amalgamated into the GTA/GreaterTorontoArea, & managability went out the window ( if your city-meeting's agenda is now over 2,000 pages long, you aren't managing anything, anymore, & that's what happened after amalgamation )

All this to say, it's probably density and area which define whether a "city" is big, or not, & not the "official boundaries" of the legal-demarcation, or the population-ignoring-density.. which don't have much relation to reality, in many cases.

( an interesting argument underlying this I came across years-ago:

The ONLY way to discover where London England actually has its limits, is to physically survey residents, & ask them whether they're in London or not, & then draw the boundaries where the residents deem themselves to be in vs out.

That the official-boundaries are .. not rooted in the citizen's actual reality.

I'd never have thought of that angle, & it's true. )

The population-density is about double, in Washington D.C., than it is in Riga, Latvia:

https://en.wikipedia.org/wiki/Washington,_D.C.

https://en.wikipedia.org/wiki/Riga

so I absolutely accept that Riga's nowhere-near as intense as Washington is.

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