To see the example at the proper size, click here
This map is based on the Kartograph software example La Bella Italia, made by Gregor Aisch.
I wondered if it was possible to do a similar map, but using D3js instead of Kartograph. I think that the result is quite similar (even with the sailing ferry!).
The technical details are in this post at GeoExamples.
The geographical data is taken from Natural Earth