https://leafletjs.com https://leafletjs.com ? If there is a lot of data, you have to take the zoom-level into consideration and aggregate the data on the serve

https://leafletjs.com https://leafletjs.com ? If there is a lot of data, you have to take the zoom-level into consideration and aggregate the data on the server side. Most news papers I have seen use LeafletJS, and Wikipedia are using it