usar json data en un google maps

[mktalternativa]

hola quiero tomar los diferentes registros que tengo en un json en este codigo de google maps en la variable "beaches" que puedo hacer?

Código:

  <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>
    <script>
// The following example creates complex markers to indicate beaches near
// Sydney, NSW, Australia. Note that the anchor is set to
// (0,32) to correspond to the base of the flagpole.

function initialize() {
  var mapOptions = {
    zoom: 13,
    center: new google.maps.LatLng(-34.800787, -58.388517)
  }
  var map = new google.maps.Map(document.getElementById('map-canvas'),
                                mapOptions);

  setMarkers(map, beaches);
}

/**
 * Data for the markers consisting of a name, a LatLng and a zIndex for
 * the order in which these markers should display on top of each
 * other.
 */
var beaches = [
  ['Bondi Beach', -34.797615, -58.362940, 5],
  ['Coogee Beach', -34.815515, -58.365601, 4],
  ['Cronulla Beach', -34.781813, -58.347786, 3],
  ['Manly Beach', -34.779275, -58.365295, 2],
  ['Maroubra Beach', -34.802324, -58.338860, 1]
];

function setMarkers(map, locations) {
  // Add markers to the map

  // Marker sizes are expressed as a Size of X,Y
  // where the origin of the image (0,0) is located
  // in the top left of the image.

  // Origins, anchor positions and coordinates of the marker
  // increase in the X direction to the right and in
  // the Y direction down.
  var image = {
    url: 'wp-content/themes/brownplus/img/beachflag.png',
    // This marker is 20 pixels wide by 32 pixels tall.
    size: new google.maps.Size(32, 32),
    // The origin for this image is 0,0.
    origin: new google.maps.Point(0,0),
    // The anchor for this image is the base of the flagpole at 0,32.
    anchor: new google.maps.Point(32, 32)
  };
  // Shapes define the clickable region of the icon.
  // The type defines an HTML &lt;area&gt; element 'poly' which
  // traces out a polygon as a series of X,Y points. The final
  // coordinate closes the poly by connecting to the first
  // coordinate.
  var shape = {
      coord: [1, 1, 1, 20, 18, 20, 18 , 1],
      type: 'poly'
  };
  for (var i = 0; i < locations.length; i++) {
    var beach = locations[i];
    var myLatLng = new google.maps.LatLng(beach[1], beach[2]);
    var marker = new google.maps.Marker({
        position: myLatLng,
        map: map,
        icon: image,
        shape: shape,
        title: beach[0],
        zIndex: beach[3]
    });
  }
}

google.maps.event.addDomListener(window, 'load', initialize);

    </script>