function initialize() {
  if (GBrowserIsCompatible()) {
    var map = new GMap2(document.getElementById("contact-map"));
    var openon = new GLatLng(51.493408,-0.226271);
    map.setCenter(openon, 13);
    map.addControl(new GSmallMapControl());
    map.addControl(new GMapTypeControl());

    // Create our "tiny" marker icon
    var onIcon = new GIcon(G_DEFAULT_ICON);
    onIcon.image = "http://www.openon.co.uk.php5-3.dfw1-1.websitetestlink.com/on_map.png";
    onIcon.iconSize = new GSize(36, 40);
    onIcon.shadowSize = new GSize(0, 0);
    onIcon.iconAnchor = new GPoint(18, 40);

    var markeroptions = { icon: onIcon }
    
    var latlng = new GLatLng(51.493408,-0.226271);
    var marker = new GMarker(openon, markeroptions);

    map.addOverlay(marker);
  }
}

window.onload = initialize;