I have created an application, available on GitHub, that allows me to split areas of the United States into subregions based on US Census population and boundary data. One of my first uses of this app was to replace the four counties of Long Island into four subregions based on my app’s algorithm rather than by the historical accidents that created the four extant counties. Background Long Island has four counties: Kings, Queens, Nassau, and Suffolk*. Portions of the boundaries of these counties are demarcated by physical features, such as the Newtown Creek between Kings County (the borough of Brooklyn) and Queens, or Cold Spring Harbor between Nassau and Suffolk. But mostly the counties are separated by political boundaries which were drawn over 350 years ago to establish county and town-level governing institutions in the colony, and later the state, of New York. ...