Embedding Google Maps - With multiple markers

Question

I am trying to embed a map into my website with multiple locations marked on it. This is the code I have for the map section, please can someone help as it stopped working once I added the third location.

                <!-- map - -->

                <div id="map"></div>
                 <script> 
            function initMap() {
            var map = new google.maps.Map(document.getElementById('map'), {
            zoom: 4,
             center: {lat: 47.852163, lng: 16.526384}

             });



            var contentString1= '<div id="content">'+
           '<div id="siteNotice">'+
            '</div>'+
            '<h1>Caravan Salon</h1>'+
             '<div>'+
             '<p><b>Messe Düsseldorf, Arena-Straße, GERMANY, 40474 </b> <br> 25th Aug - 3rd Sept, 2017 <br> <a href="http://www.caravan-salon.com" target="_blank">http://www.caravan-salon.com/</a>    </p>'+
             '</div>'+
             '</div>';

             var infowindow1 = new google.maps.InfoWindow({
              content: contentString1
            });
            // Caravan Salon
             var marker1 = new google.maps.Marker({
            position: {lat: 51.263620, lng:  6.735830},
             map: map
             });


             marker1.addListener('click', function() {

             infowindow1.open(map, marker1);
            });





                var contentString2 = '<div id="content">'+
                '<div id="siteNotice">'+
                '</div>'+
                '<h1 id="firstHeading" class="firstHeading">Thomas Gieger Pop up Caravans</h1>'+
                '<div id="bodyContent">'+
                '<p><b> Hummelbühel 569, 7000 Eisenstadt, Austria</b> <br> office@caravan-sharing.at <br> 00430 6769406043<br> <a href="http://www.caravan-sharing.at/" target="_blank">http://www.caravan-sharing.at/</a> </p>'+
                '</div>'+
                '</div>';


                var infowindow2 = new google.maps.InfoWindow({
                content: contentString2
                });
                // Thomas Gieger 
                var marker2 = new google.maps.Marker({
                position: {lat: 47.852163, lng: 16.526384},
                map: map     

                });
                marker2.addListener('click', function() {

                infowindow2.open(map, marker2);

                });


                var contentString3= '<div id="content">'+
                '<div id="siteNotice">'+
                '</div>'+
                '<h1>Camping and Caravaning Rostock 2017</h1>'+
                '<div>'+
                '<p><b> HanseMesse Rostock, Zur HanseMesse 1-2, 18106 Rostock, GERMANY </b> <br> 17th March - 19th March, 2017  </p>'
                '</div>'+
                '</div>';

                var infowindow3 = new google.maps.InfoWindow({
                content: contentString3
                });
                // Camping and Caravaning Rostock 2017
                var marker3 = new google.maps.Marker({
                position: {lat: 54.138845, lan 12.073279}
                map: map
                });


                marker3.addListener('click', function() {

                infowindow3.open(map, marker3);
                 }); 





                }
                </script>







                <script async defer
                 src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCbKJArdmwTF9-_qQa10SovlgJO2kNRo9c&callback=initMap">
                 </script>

Answer 1

missing comma after position in marker3

    var infowindow3 = new google.maps.InfoWindow({
      content: contentString3
    });
    // Camping and Caravaning Rostock 2017
    var marker3 = new google.maps.Marker({
      position: {lat: 54.138845, lan 12.073279}, //  here 
      map: map
    });

Answer 2

I get a javascript error with the posted code: Uncaught SyntaxError: Unexpected number

There are multiple errors:

1. missing comma after the position in marker3
2. missing ":" after member lan of position
3. lan member should be lng

proof of concept fiddle

working code snippet:

html,
body,
#map {
  height: 100%;
  width: 100%;
  margin: 0px;
  padding: 0px
}

<!-- map - -->
<div id="map"></div>
<script>
  function initMap() {
    var map = new google.maps.Map(document.getElementById('map'), {
      zoom: 4,
      center: {
        lat: 47.852163,
        lng: 16.526384
      }
    });

    var contentString1 = '<div id="content">' +
      '<div id="siteNotice">' +
      '</div>' +
      '<h1>Caravan Salon</h1>' +
      '<div>' +
      '<p><b>Messe Düsseldorf, Arena-Straße, GERMANY, 40474 </b> <br> 25th Aug - 3rd Sept, 2017 <br> <a href="http://www.caravan-salon.com" target="_blank">http://www.caravan-salon.com/</a>    </p>' +
      '</div>' +
      '</div>';

    var infowindow1 = new google.maps.InfoWindow({
      content: contentString1
    });
    // Caravan Salon
    var marker1 = new google.maps.Marker({
      position: {
        lat: 51.263620,
        lng: 6.735830
      },
      map: map
    });

    marker1.addListener('click', function() {
      infowindow1.open(map, marker1);
    });

    var contentString2 = '<div id="content">' +
      '<div id="siteNotice">' +
      '</div>' +
      '<h1 id="firstHeading" class="firstHeading">Thomas Gieger Pop up Caravans</h1>' +
      '<div id="bodyContent">' +
      '<p><b> Hummelbühel 569, 7000 Eisenstadt, Austria</b> <br> office@caravan-sharing.at <br> 00430 6769406043<br> <a href="http://www.caravan-sharing.at/" target="_blank">http://www.caravan-sharing.at/</a> </p>' +
      '</div>' +
      '</div>';

    var infowindow2 = new google.maps.InfoWindow({
      content: contentString2
    });
    // Thomas Gieger 
    var marker2 = new google.maps.Marker({
      position: {
        lat: 47.852163,
        lng: 16.526384
      },
      map: map
    });
    marker2.addListener('click', function() {
      infowindow2.open(map, marker2);
    });

    var contentString3 = '<div id="content">' +
      '<div id="siteNotice">' +
      '</div>' +
      '<h1>Camping and Caravaning Rostock 2017</h1>' +
      '<div>' +
      '<p><b> HanseMesse Rostock, Zur HanseMesse 1-2, 18106 Rostock, GERMANY </b> <br> 17th March - 19th March, 2017  </p>'
    '</div>' +
    '</div>';

    var infowindow3 = new google.maps.InfoWindow({
      content: contentString3
    });
    // Camping and Caravaning Rostock 2017
    var marker3 = new google.maps.Marker({
      position: {
        lat: 54.138845,
        lng: 12.073279
      },
      map: map
    });

    marker3.addListener('click', function() {
      infowindow3.open(map, marker3);
    });
  }
</script>
<script async defer src="https://maps.googleapis.com/maps/api/js?callback=initMap"></script>