<div id="map"></div>
<script>
  var map;
  function initMap() {
    map = new google.maps.Map(
        document.getElementById('map'),
        {center: new google.maps.LatLng(-33.91722, 151.23064), zoom: 16});

    var iconBase =
        'https://developers.google.com/maps/documentation/javascript/examples/full/images/';

    var icons = {
      parking: {
        icon: iconBase + 'parking_lot_maps.png'
      },
      library: {
        icon: iconBase + 'library_maps.png'
      },
      info: {
        icon: iconBase + 'info-i_maps.png'
      }
    };

    var features = [
      {
        position: new google.maps.LatLng(-33.91721, 151.22630),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91539, 151.22820),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91747, 151.22912),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91910, 151.22907),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91725, 151.23011),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91872, 151.23089),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91784, 151.23094),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91682, 151.23149),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91790, 151.23463),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91666, 151.23468),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.916988, 151.233640),
        type: 'info'
      }, {
        position: new google.maps.LatLng(-33.91662347903106, 151.22879464019775),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.916365282092855, 151.22937399734496),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.91665018901448, 151.2282474695587),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.919543720969806, 151.23112279762267),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.91608037421864, 151.23288232673644),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.91851096391805, 151.2344058214569),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.91818154739766, 151.2346203981781),
        type: 'parking'
      }, {
        position: new google.maps.LatLng(-33.91727341958453, 151.23348314155578),
        type: 'library'
      }
    ];

    // Create markers.
    for (var i = 0; i < features.length; i++) {
      var marker = new google.maps.Marker({
        position: features[i].position,
        icon: icons[features[i].type].icon,
        map: map
      });
    };
  }
</script>
<script async defer
src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap">
</script>

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