Getting the URL for every language
I found the solution myself, with the following code.

// Get all languages of the site
$languages = \Drupal::languageManager()-&gt;getLanguages();

// Route of contact for example:
$route = 'contact.site_page';
foreach ($languages as $language) {
  $url = new Url($route, [], ['language' =&gt; $language]);
  $uri = $url-&gt;toString();
}