This map shows the population of cities worldwide as scaled symbols overlaid on a geographic projection. Using React with D3 v6, it renders a Natural Earth projection with graticules and land boundaries via `geoNaturalEarth1` and `geoPath`. City populations are encoded as circle radii using a square root scale (`scaleSqrt`) ranging up to 15 pixels, with the data sourced from a cleaned world cities CSV file. The visualization demonstrates a hybrid React-D3 approach, where D3 handles the mathematical projection and scaling while React manages the SVG markup and component lifecycle.