Calculate distance between two cities using google maps API

directions.txt

{
   "routes" : [
      {
         "bounds" : {
            "northeast" : {
               "lat" : 4.3561,
               "lng" : 1.01389
            },
            "southwest" : {
               "lat" : 9.293703,
               "lng" : 5.96733
            }
         },
         "copyrights" : "Map data ©2014 Google",
         "legs" : [
            {
               "distance" : {
                  "text" : "9.4 km",
                  "value" : 9356
               },
               "duration" : {
                  "text" : "11 mins",
                  "value" : 651
               },
               "end_address" : "Brno, Czech Republic",
               "end_location" : {
                  "lat" : 49.3561181,
                  "lng" : 16.0130389
               },
        ...
      }
   ],
   "status" : "OK"
}

google_maps_distance.php

<?php

$from = 'Praha';
$to   = 'Brno';

// @link https://developers.google.com/maps/signup?hl=cs
$key = 'AI...KEY...';

$url = 'https://maps.googleapis.com/maps/api/directions/json?origin=%s&destination=%s&sensor=false&key=%s';

$contents = file_get_contents(sprintf($url, urlencode($from), urlencode($to), $key));

// output the response into a file or echo it
file_put_contents('directions.txt', $contents);

$json = json_decode($contents, true);


$from = $json['routes'][0]['legs'][0]['start_address'];
$to   = iconv('UTF-8', 'windows-1250//TRANSLIT', $json['routes'][0]['legs'][0]['end_address']);
$totalDistance = $json['routes'][0]['legs'][0]['distance']['text'];

echo "$from -> $to total: $totalDistance.";