In this article I will explain with example, how to add multiple in Google Map using JavaScript and Google Maps API V3.
 
 
Adding multiple markers with InfoWindow to Google Map
The following code snippet consists of an array of markers of different geographic address locations. Each marker in the array contains title, latitude, longitude and description of the location.
Inside the window.onload event handler, the LoadMap function is executed.
A loop is executed over the array of markers and one by one each marker is populated on the Google Map.
Inside the loop, a click event listener is added to each Google Map marker. Inside the click event handler, the Google Maps InfoWindow is shown with the contents.
Finally the Google Map is displayed using the HTML DIV element.
<script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?sensor=false"></script>
<script type="text/javascript">
    var markers = [
    {
        "title": 'Aksa Beach',
        "lat": '19.1759668',
        "lng": '72.79504659999998',
        "description": 'Aksa Beach is a popular beach and a vacation spot in Aksa village at Malad, Mumbai.'
    },
    {
        "title": 'Juhu Beach',
        "lat": '19.0883595',
        "lng": '72.82652380000002',
        "description": 'Juhu Beach is one of favourite tourist attractions situated in Mumbai.'
    },
    {
        "title": 'Girgaum Beach',
        "lat": '18.9542149',
        "lng": '72.81203529999993',
        "description": 'Girgaum Beach commonly known as just Chaupati is one of the most famous public beaches in Mumbai.'
    },
    {
        "title": 'Jijamata Udyan',
        "lat": '18.979006',
        "lng": '72.83388300000001',
        "description": 'Jijamata Udyan is situated near Byculla station is famous as Mumbai (Bombay) Zoo.'
    },
    {
        "title": 'Sanjay Gandhi National Park',
        "lat": '19.2147067',
        "lng": '72.91062020000004',
        "description": 'Sanjay Gandhi National Park is a large protected area in the northern part of Mumbai city.'
    }
    ];
    window.onload = function () {
        LoadMap();
    }
    function LoadMap() {
        var mapOptions = {
            center: new google.maps.LatLng(markers[0].lat, markers[0].lng),
            zoom: 10,
            mapTypeId: google.maps.MapTypeId.ROADMAP
        };
        var map = new google.maps.Map(document.getElementById("dvMap"), mapOptions);
 
        //Create and open InfoWindow.
        var infoWindow = new google.maps.InfoWindow();
 
        for (var i = 0; i < markers.length; i++) {
            var data = markers[i];
            var myLatlng = new google.maps.LatLng(data.lat, data.lng);
            var marker = new google.maps.Marker({
                position: myLatlng,
                map: map,
                title: data.title
            });
 
            //Attach click event to the marker.
            (function (marker, data) {
                google.maps.event.addListener(marker, "click", function (e) {
                    //Wrap the content inside an HTML DIV in order to set height and width of InfoWindow.
                    infoWindow.setContent("<div style = 'width:200px;min-height:40px'>" + data.description + "</div>");
                    infoWindow.open(map, marker);
                });
            })(marker, data);
        }
    }
</script>
<div id="dvMap" style="width: 300px; height: 400px">
</div>
 
 
Screenshot
Google Maps API V3: Add marker in Google Map using JavaScript
 
 
Demo
View Demo
 
 
Downloads

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