Map pattern · POC

Rome

Tiles: OpenFreeMap (openfreemap.org) — vector tiles, free, no key required. Styles: Liberty (streets), Positron (minimal), Bright.
Renderer: MapLibre GL 4 — open-source fork of Mapbox GL JS. CSS: maplibre-gl/dist/maplibre-gl.css .
Markers: HTML &lt;button&gt; via new maplibregl.Marker(&#123; element &#125;) ; popups via maplibregl.Popup() .
Polygons: GeoJSON sources at /geo/rome-*.geojson ; visibility toggled via map.setLayoutProperty() .
Style switch: map.setStyle() clears user layers; polygon layers re-added on map.once('idle', ...) .

MapLibre GL + OpenFreeMap — 20 markers, 4 layers, 2 polygon overlays. Pan, zoom, click. No API key required

Provider: OpenFreeMap (free · community-hosted) Compare: MapTiler Mapbox

3D and Street View powered by Google Maps — free forever via Maps Embed API. No API key required.