var layerBaseStreet = "http://mapsrv2.terra.gr/ArcGIS/rest/services/CityGuides/kalithea121009/MapServer";
var layerBaseSat = "http://mapsrv2.terra.gr/ArcGIS/rest/services/CityGuides/kalitheaSat121009/MapServer";
var layerBaseHybrid = "http://mapsrv2.terra.gr/ArcGIS/rest/services/CityGuides/kalitheaHybr121009/MapServer";