var map;
    var InnlocationmapGeoXML; 
    var TransportationmapGeoXML; 
    var RecreationmapGeoXML; 
    var AttractionsmapGeoXML; 
    var DiningmapGeoXML; 
    var HistoricsitesmapGeoXML; 

    // initialize state variables
    var InnlocationmapToggleState = 0;
    var TransportationmapToggleState = 0;
    var RecreationmapToggleState = 0;
    var AttractionsmapToggleState = 0;
    var DiningmapToggleState = 0;
    var HistoricsitesmapToggleState = 0;

    function initialize_google_map()
    {
      if (GBrowserIsCompatible())
      {
        // initialize KML overlay 
        InnlocationmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/innlocation.kml");
        TransportationmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/transportation.kml");
        RecreationmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/recreation.kml");
        AttractionsmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/attractions.kml");
        DiningmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/dining.kml");
        HistoricsitesmapGeoXML = new GGeoXml("http://www.longingforhome.com/google-maps/historic-sites.kml");

        // initialize map and add the default area attractions overlay
        map = new GMap2(document.getElementById("map_canvas")); 
        map.setCenter(new GLatLng(34.830221, -87.304208), 10); 
        map.addControl(new GLargeMapControl());
        map.addControl(new GMapTypeControl());

        InnlocationmapToggleState = 1;
        map.addOverlay(InnlocationmapGeoXML);

        TransportationmapToggleState = 1;
        map.addOverlay(TransportationmapGeoXML);

      }
    } 


    function TurnOnTransportationmap()
    {
      if(0 == TransportationmapToggleState)
      {
        map.addOverlay(TransportationmapGeoXML);
        TransportationmapToggleState = 1;
      }
    }

    function TurnOffTransportationmap()
    {
      if(1 == TransportationmapToggleState)
      {
        map.removeOverlay(TransportationmapGeoXML);
        TransportationmapToggleState = 0;
      }
    }

    function TurnOnRecreationmap()
    {
      if(0 == RecreationmapToggleState)
      {
        map.addOverlay(RecreationmapGeoXML);
        RecreationmapToggleState = 1;
      }
    }

    function TurnOffRecreationmap()
    {
      if(1 == RecreationmapToggleState)
      {
        map.removeOverlay(RecreationmapGeoXML);
        RecreationmapToggleState = 0;
      }
    }

    function TurnOnAttractionsmap()
    {
      if(0 == AttractionsmapToggleState)
      {
        map.addOverlay(AttractionsmapGeoXML);
        AttractionsmapToggleState = 1;
      }
    }

    function TurnOffAttractionsmap()
    {
      if(1 == AttractionsmapToggleState)
      {
        map.removeOverlay(AttractionsmapGeoXML);
        AttractionsmapToggleState = 0;
      }
    }

    function TurnOnDiningmap()
    {
      if(0 == DiningmapToggleState)
      {
        map.addOverlay(DiningmapGeoXML);
        DiningmapToggleState = 1;
      }
    }

    function TurnOffDiningmap()
    {
      if(1 == DiningmapToggleState)
      {
        map.removeOverlay(DiningmapGeoXML);
        DiningmapToggleState = 0;
      }
    }

   function TurnOnHistoricsitesmap()
    {
      if(0 == HistoricsitesmapToggleState)
      {
        map.addOverlay(HistoricsitesmapGeoXML);
        HistoricsitesmapToggleState = 1;
      }
    }

    function TurnOffHistoricsitesmap()
    {
      if(1 == HistoricsitesmapToggleState)
      {
        map.removeOverlay(HistoricsitesmapGeoXML);
        HistoricsitesmapToggleState = 0;
      }
    }