function initialize() {
 
  if (GBrowserIsCompatible()) {
    var map = new GMap2(document.getElementById("map_canvas"));
    map.addControl(new GSmallMapControl());
    map.addControl(new GMapTypeControl());
    map.setCenter(new GLatLng(52.2702978, 20.9740533), 15);
  
    // Creates a marker at the given point
    // Clicking the marker will hide it
    function createMarker(point, number) {
      var marker = new GMarker(point);
      marker.value = number;
      GEvent.addListener(marker,"click", function() {
        var myHtml = "<div style='font-size: 18px;'><b>Centrum Nurkowe Crazy Shark<br>Warszawa</b><br>ul. Popiełuszki 19/21<br>tel. (22) 833-33-50 </div>";
        map.openInfoWindowHtml(point, myHtml);
      });
	  return marker;
    }
    
      var point = new GLatLng(52.2702978,20.9740533);
	  map.addOverlay(createMarker(point, 0));
  }
}