Мультиязычность в Laravel

Использовать prefix с middleware - примерно такой код будет в routes.php

Route::get('/signout', ['as' => 'auth.signout', 'uses' => 'Auth\AuthController@signout']);
Route::get('/login', ['as' => 'auth.login', 'uses' => 'Auth\AuthController@login']);
Route::post('/create', ['as' => 'auth.create', 'uses' => 'Auth\AuthController@create']);
Route::post('/signin', ['as' => 'auth.signin', 'uses' => 'Auth\AuthController@signin']);
Route::get('/', function(){
    return Redirect::to('/ro');
});
Route::group(['middleware' => 'isAdmin:admin', 'namespace' => 'Admin'], function(){
    //...
});
Route::group(['middleware' => 'Localization'], function() {
    Route::get('/{lang}/offers/view/{offer_id}', ['as' => 'offers.view', 'uses' => 'OffersController@view']);
    Route::get('/{lang}/news/view/{offer_id}', ['as' => 'news.view', 'uses' => 'NewsController@view']);
});
Route::group(['prefix' => '{lang}', 'middleware' => 'Localization'], function() {
    Route::get('/', ['as' => 'site.index', 'uses' => 'SiteController@index']);
    Route::get('/contacts', ['as' => 'site.contacts', 'uses' => 'SiteController@contacts']);
    Route::get('/offers', ['as' => 'offers.index', 'uses' => 'OffersController@index']);
    Route::get('/news', ['as' => 'news.index', 'uses' => 'NewsController@index']);
    Route::get('/info', ['as' => 'site.info', 'uses' => 'SiteController@info']);
    Route::get('/info2', ['as' => 'site.info2', 'uses' => 'SiteController@info2']);
    Route::get('/info3', ['as' => 'site.info3', 'uses' => 'SiteController@info3']);
    Route::get('/info4', ['as' => 'site.info4', 'uses' => 'SiteController@info4']);
    Route::get('/payments', ['as' => 'site.payments', 'uses' => 'SiteController@payments']);
});

Самый простой способ - воспользоваться специальным middleware: laravel-localization

Нужно обернуть группу роутов, которые вы хотите префиксовать в функцию:

// app/Http/routes.php
// тут обрабатываются URL с префиксами.
Route::group(['prefix' => LaravelLocalization::setLocale()], function()
{
    /** ADD ALL LOCALIZED ROUTES INSIDE THIS GROUP **/
    Route::get('/', function()
    {
        return View::make('hello');
    });
    Route::get('test',function(){
        return View::make('test');
    });
});
/** OTHER PAGES THAT SHOULD NOT BE LOCALIZED **/

Дополнительные сведения читайте в документации.