$origin = "Rome, Italy";
$destination = "Venice, Italy";
$key = "YOUR-OWN-KEY";
$url = "https://maps.googleapis.com/maps/api/directions/json?origin=".urlencode($origin).",IL&destination=" . urlencode( $destination) . "&sensor=false&key=" . $key;
$jsonfile = file_get_contents($url);
$jsondata = json_decode($jsonfile);
print_r( $jsondata->routes[0]->legs[0]->distance);