function initialize() {
    var thisMapTypeID = google.maps.MapTypeId.ROADMAP;
    var zoomLevel = parseInt(document.getElementById("ZoomLevel").value);
    var lat = parseFloat(document.getElementById("Latitude").value);
    var lng = parseFloat(document.getElementById("Longitude").value);
    if ((lat < -90) || (lat > 90) || (lng < -180) || (lng > 180)) {
        lat = 0.0;
        lng = 0.0;
    }
    var mapCenter = new google.maps.LatLng(lat, lng);
    var myOptions = {
            zoom: zoomLevel,
            center: mapCenter,
            mapTypeId: thisMapTypeID
        };
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

    //
    // Draw site marker
    //

    sitemarker = new google.maps.Marker({
        position: mapCenter,
        map: map
    });

}