A world map displays cities as brown circles, with circle size proportional to each city’s population using a square-root scale. A dropdown menu lets users select the number of cities shown, from a radius setting to top 10, 50, or 200 cities. The visualization uses d3.geoNaturalEarth1 and d3.geoPath for map projections, d3.scaleSqrt for sizing, and React for the interface. City data comes from the Data Canvas Sense Your City dataset, loaded via d3.csv.