I'm used to thinking in terms of national borders, but this shows how the population is organized by the Tigris and Euphrates, not by artificial lines on a map.
ISIL understands this well, making the Iraq/Syria border into a pretty meaningless imaginary line. The ISIL blitz seems like it came from nowhere, but this dramatically illustrates their methodical progression, over time, following the rivers.
I found myself wanting to know more about the communities, lakes, dams, roads, borders, sects, nationalities other features highlighted in this piece, so I spent another hour manually linking to Google Earth and Wikipedia to drill into more detail.
Along the way I found a lot of content on YouTube of ISIL takeovers of cities, burning of vehicles and disturbing images of executions and crucifixions. I'd seen some of this before, but it would be really powerful to link selected videos and images from the ground directly to places on the map.
I'd be interested in the editorial process at the NYT, how this evolved from idea to realization, who supplied the content, and how the development team coordinated with the reporters.
And I'd like to understand more about how the autonomous Kurdish region fits into this story, both geographically as well as politically and militarily.