diff --git a/core/modules/system/lib/Drupal/system/Controller/AdminController.php b/core/modules/system/lib/Drupal/system/Controller/AdminController.php
new file mode 100644
index 0000000..6bda138
--- /dev/null
+++ b/core/modules/system/lib/Drupal/system/Controller/AdminController.php
@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\system\Controller\AdminController.
+ */
+
+namespace Drupal\system\Controller;
+
+use Drupal\Core\Controller\ControllerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Controller for admin section.
+ */
+class AdminController implements ControllerInterface {
+
+  /**
+   * Module handler service.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Constructs an AdminController object.
+   *
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   Module Handler Service.
+   */
+  public function __construct(ModuleHandlerInterface $module_handler) {
+    $this->moduleHandler = $module_handler;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('module_handler')
+    );
+  }
+
+  /**
+   * Prints a listing of admin tasks, organized by module.
+   *
+   * @return array
+   *  A render array containing the listing.
+   */
+  public function index() {
+    $module_info = system_get_info('module');
+    foreach ($module_info as $module => $info) {
+      $module_info[$module] = new \stdClass();
+      $module_info[$module]->info = $info;
+    }
+
+    $this->moduleHandler->loadInclude('system', 'admin.inc');
+
+    uasort($module_info, 'system_sort_modules_by_info_name');
+    $menu_items = array();
+
+    foreach ($module_info as $module => $info) {
+      // Only display a section if there are any available tasks.
+      if ($admin_tasks = system_get_module_admin_tasks($module, $info->info)) {
+        // Sort links by title.
+        uasort($admin_tasks, 'drupal_sort_title');
+        // Move 'Configure permissions' links to the bottom of each section.
+        $permission_key = "admin/people/permissions#module-$module";
+        if (isset($admin_tasks[$permission_key])) {
+          $permission_task = $admin_tasks[$permission_key];
+          unset($admin_tasks[$permission_key]);
+          $admin_tasks[$permission_key] = $permission_task;
+        }
+
+        $menu_items[$info->info['name']] = array($info->info['description'], $admin_tasks);
+      }
+    }
+
+    $output = array(
+      '#theme' => 'system_admin_index',
+      '#menu_items' => $menu_items,
+    );
+
+    return $output;
+  }
+}
diff --git a/core/modules/system/system.admin.inc b/core/modules/system/system.admin.inc
index 1566c80..6761689 100644
--- a/core/modules/system/system.admin.inc
+++ b/core/modules/system/system.admin.inc
@@ -90,37 +90,6 @@ function system_admin_menu_block_page() {
 }
 
 /**
- * Menu callback; prints a listing of admin tasks, organized by module.
- */
-function system_admin_index() {
-  $module_info = system_get_info('module');
-  foreach ($module_info as $module => $info) {
-    $module_info[$module] = new stdClass();
-    $module_info[$module]->info = $info;
-  }
-  uasort($module_info, 'system_sort_modules_by_info_name');
-  $menu_items = array();
-
-  foreach ($module_info as $module => $info) {
-    // Only display a section if there are any available tasks.
-    if ($admin_tasks = system_get_module_admin_tasks($module, $info->info)) {
-      // Sort links by title.
-      uasort($admin_tasks, 'drupal_sort_title');
-      // Move 'Configure permissions' links to the bottom of each section.
-      $permission_key = "admin/people/permissions#module-$module";
-      if (isset($admin_tasks[$permission_key])) {
-        $permission_task = $admin_tasks[$permission_key];
-        unset($admin_tasks[$permission_key]);
-        $admin_tasks[$permission_key] = $permission_task;
-      }
-
-      $menu_items[$info->info['name']] = array($info->info['description'], $admin_tasks);
-    }
-  }
-  return theme('system_admin_index', array('menu_items' => $menu_items));
-}
-
-/**
  * Menu callback; displays a listing of all themes.
  */
 function system_themes_page() {
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 0d472e5..44e5b00 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -669,11 +669,9 @@ function system_menu() {
   );
   $items['admin/index'] = array(
     'title' => 'Index',
-    'page callback' => 'system_admin_index',
-    'access arguments' => array('access administration pages'),
+    'route_name' => 'system_admin_index',
     'type' => MENU_LOCAL_TASK,
     'weight' => -18,
-    'file' => 'system.admin.inc',
   );
 
   // Menu items that are basically just menu blocks.
diff --git a/core/modules/system/system.routing.yml b/core/modules/system/system.routing.yml
index 9859d6a..5f66188 100644
--- a/core/modules/system/system.routing.yml
+++ b/core/modules/system/system.routing.yml
@@ -87,3 +87,10 @@ date_format_localize_reset:
     _form: '\Drupal\system\Form\DateFormatLocalizeResetForm'
   requirements:
     _permission: 'administer site configuration'
+
+system_admin_index:
+  pattern: 'admin/index'
+  defaults:
+    _content: 'Drupal\system\Controller\AdminController::index'
+  requirements:
+    _permission: 'access administration pages'