So administrator should be able to login and upload an xml from backend. When uploaded WordPress it self would then add each of the cordinates to right page's google maps.
Example of xml file.
First goes city name/wordpress page name and then cordinates for that place in that city.
Amsterdam - 52.372620, 4.820508
Barcelona - 41.403224, 2.174260
So my two questions are 1. Is there any plugins to make this job easier 2. How would you do this ?
You can use the iframe API. All you need to do in your Wordpress PHP is to add
<iframe
width="600"
height="450"
frameborder="0" style="border:0"
src="https://www.google.com/maps/embed/v1/place?key=YOUR_API_KEY&q="+YOUR_LAT_LNG allowfullscreen>
</iframe>
onto your page. You will also need to apply for an API key in the Google Developers Console. Check here for instruction https://developers.google.com/maps/documentation/embed/guide#api_key