function initialize() {
  if (GBrowserIsCompatible()) {
    var map = new GMap2(document.getElementById("map_canvas"));    
    var center = new GLatLng(45.482962, 9.199414);
    var htmlText = "Via Fabio Filzi, 8 <br/>20124 Milano <br/>ITALY";
    var marker = new GMarker(center, {draggable: false});
    
    map.setCenter(center, 16);
    map.setUIToDefault();
    
    GEvent.addListener(marker, "click", function() {
      marker.openInfoWindowHtml(htmlText);
    })
    map.addOverlay(marker);
    
    GEvent.trigger(marker, 'click');
  }
  
}

YAHOO.util.Event.addListener(window, 'load', initialize);