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I'd like to get a nice silhouette of the land area of the US lower 48 states using Mathematica's GeoGraphics method. I tried:

bounds = GeoBounds[United States (country)];
GeoGraphics[{GeoStyling[RGBColor[.1,.1,.3], Opacity[1]],Polygon[United States]}, GeoRange->bounds, GeoBackground->White]

But I get a big blob where Michigan, Minnesota, and Wisconsin territory includes the Great Lakes: Michigan!  Where are you?

I'd like to make a silhouette that very clearly defines the land area of the US. I've tried "subtracting" out the Great Lakes as so:

bounds = GeoBounds[United States (country)];
GeoGraphics[{GeoStyling[RGBColor[.1,.1,.3], Opacity[1]],Polygon[United States],GeoStyling[White, Opacity[1]],Polygon[Lake Michigan  (lake)]}, GeoRange->bounds, GeoBackground->White]

But there's no polygon data for any of the Great Lakes. Thoughts/comments? Thanks!

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This ought to do it:

GeoGraphics[{GeoStyling[RGBColor[0.1, 0.1, 0.3], Opacity[1]], 
  EntityClass["AdministrativeDivision", "ContinentalUSStates"][
   "Polygon"]}, GeoBackground -> None]

enter image description here

What was needed was a different Entity (or rather in this case an EntityClass). This is a collection of US states, so I suspect it has information about their individual borders, rather than the whole US as a single unit.

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  • $\begingroup$ but it does look like something strange is happening with Louisiana... $\endgroup$ – chuy Oct 14 '15 at 14:14
  • $\begingroup$ When you make a larger sized graphic in Mathematica, Louisiana starts to look a little better. Thanks -- exactly what I was looking for. $\endgroup$ – Mike Oct 14 '15 at 14:19
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    $\begingroup$ I live in Michigan and this matter of state borders comes up all the time. The official answer, as I understand it, is the borders of the state truly run through the lakes. States end at the water's edge along the oceans, but not in the Great Lakes. So what you getting are the legal borders. I am not a lawyer, but I've heard this argued enough to think I've got it right. $\endgroup$ – m_goldberg Oct 14 '15 at 14:20
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    $\begingroup$ @m_goldberg This makes sense, it's not as if there would be a pocket of international waters in the middle of Lake Michigan. Otherwise there would be a much bigger and booming part boat industry in the Great Lakes. "Come party down in Lake Erie this winter! What happens in Erie stays in Erie" $\endgroup$ – chuy Oct 14 '15 at 14:25
  • $\begingroup$ google.com/maps/place/Illinois/@41.5604499,-88.7378851,7.25z/… the dashed lines in lake Michigan are the state borders, and the solid lines in the other great likes appear to be the border between US and Canada $\endgroup$ – chiliNUT Oct 14 '15 at 17:06

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