This example displays an interactive map of India with markers positioned in multiple major cities, including Delhi, Mumbai, Kolkata, and Chennai. The map is built using the MapmyIndia API with a vector layer, and D3.js v7 is used to overlay an SVG circle centered on Delhi with a 10,000-meter radius. The circle’s position updates dynamically on map movement via the `map.on("moveend", update)` event, projecting geographic coordinates to screen space using the `map.project` method. Leaflet, jQuery, and a hardcoded array of latitude-longitude pairs define the marker placements.