The incorporation of Binghamton united various communities on both shores of the two rivers. The majority of the city's population and development lies along the rolling terrain nearest the riverbanks with sparse development in the hills that define the city limits. The old city was laid out on a grid system by Joshua Whitney, Jr., but as development spread to the outer regions of the city and merged with other settlements, several grids were eventually juxtaposed against each other. In the Southside, the grid breaks down, as more curvilinear roads make up the predominantly residential areas along the hills.