function initialize() {
  if (GBrowserIsCompatible()) {    
    var map = new GMap2(document.getElementById("googlemaps"));
    map.setCenter(new GLatLng(51.585202, -0.279946), 11);
    var point = new GLatLng(51.585202, -0.279946);
    var marker_headoffice = new GMarker(point);
    GEvent.addListener(marker_headoffice, "click", function() {
        marker_headoffice.openInfoWindowHtml("<div align='center'><strong>ANB Constructon Limited</strong><br />Alpha House<br/>646c Kingsbury Road<br/>London<br/>NW9 9HN</div>");
    })
    map.addOverlay(marker_headoffice);
    map.setUIToDefault();   
  }
}