The other thing that nobody ever mentions is that western cities annex outlying territory to build tax base and population. They do it in the south, as well.

Denver annexed Tech Center a number of years ago (which was not contiguous to the city borders, as required by state law) by annexing the highway to the tech center and then annexing Tech Center. So you get this strange map with a lollipop - Tech Center connected to the rest of Denver by a highway and the adjacent (immediately) properties.

Perhaps Philadelphia should annex Lower Merion Twp. Hah!

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“Cities have the capability of providing something for everybody, only because, and only when, they are created by everybody.” - Jane Jacobs