function load() {
      if (GBrowserIsCompatible()) {
        var map = new GMap2(document.getElementById("map"));
        map.addControl(new GSmallMapControl());
        map.addControl(new GMapTypeControl());
        map.setCenter(new GLatLng(50.084655,8.582124), 14);

        // Creates a marker at the given point with the given number label
        function createMarker(point, refhtm) {
          var marker = new GMarker(point);
          GEvent.addListener(marker, "click", function() {
            marker.openInfoWindowHtml("<br><iframe src="+refhtm+" width='400' height='180' name='info' frameborder='0' scrolling='no'></iframe>");
          });
          return marker;
        }

        GDownloadUrl("schwanheim.xml", function(data) {
          var xml = GXml.parse(data);
          var markers = xml.documentElement.getElementsByTagName("marker");
          for (var i = 0; i < markers.length; i++) {
            var point = new GLatLng(parseFloat(markers[i].getAttribute("lat")),
                                    parseFloat(markers[i].getAttribute("lng")));
            map.addOverlay(createMarker(point, markers[i].getAttribute("ref")));
          }
        });
      }
    }