cakephp でコントローラーにアクセスできない

以下のようなエラーが出ます。

Error: Controller could not be found.

Error: Create the class Controller below in file: app/Controller/Controller.php

こちらですが、[Hello]コントーラーを作成しました。パスは、下記の通りです。
/app/Controller/HelloController.php

中身は、以下の通りです。

PHP
1<?php
2class HelloController extends AppController {
3 
4  function index() {
5    $data = 'Hello world!';
6    $this->set('data', $data);
7  }
8 
9}
10?>

こちらで、Viewを下記のパスに作成しました。
/app/View/Hello/index.ctp

がしかし、アクセスしてもエラーが出てしまいます。なぜでしょうか？

cakephpは正常に動いております。

追記(routers.php)

<?php
/**
 * Routes configuration
 *
 * In this file, you set up routes to your controllers and their actions.
 * Routes are very important mechanism that allows you to freely connect
 * different URLs to chosen controllers and their actions (functions).
 *
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @package       app.Config
 * @since         CakePHP(tm) v 0.2.9
 * @license       http://www.opensource.org/licenses/mit-license.php MIT License
 */
 
/**
 * Here, we are connecting '/' (base path) to controller called 'Pages',
 * its action called 'display', and we pass a param to select the view file
 * to use (in this case, /app/View/Pages/home.ctp)...
 */
	Router::connect('/', array('controller' => 'pages', 'action' => 'display', 'home'));
/**
 * ...and connect the rest of 'Pages' controller's URLs.
 */
	Router::connect('/pages/*', array('controller' => 'pages', 'action' => 'display'));

/**
 * Load all plugin routes. See the CakePlugin documentation on
 * how to customize the loading of plugin routes.
 */
	CakePlugin::routes();

/**
 * Load the CakePHP default routes. Only remove this if you do not want to use
 * the built-in default routes.
 */