A map visualization plots world cities with populations exceeding 50,000 as sized points, using a square-root scale to encode population via circle radius. The map uses `geoNaturalEarth1` projection with `geoPath` for land, graticules, and country interiors. City data comes from Simplemaps’ World Cities Database, rendered in React with SVG circles. The visualization is built with d3.v5, featuring a clean, light-styled map with semi-transparent teal circles showing population distribution globally.