diff --git a/core/modules/block/custom_block/custom_block.module b/core/modules/block/custom_block/custom_block.module
index 0a3efde..a35b5ef 100644
--- a/core/modules/block/custom_block/custom_block.module
+++ b/core/modules/block/custom_block/custom_block.module
@@ -90,14 +90,10 @@ function custom_block_menu() {
   );
   $items['block/%custom_block/delete'] = array(
     'title' => 'Delete',
-    'page callback' => 'drupal_get_form',
-    'page arguments' => array('custom_block_delete_form', 1),
-    'access callback' => 'entity_page_access',
-    'access arguments' => array(1, 'delete'),
     'weight' => 1,
     'type' => MENU_LOCAL_TASK,
     'context' => MENU_CONTEXT_INLINE,
-    'file' => 'custom_block.pages.inc',
+    'route_name' => 'custom_block_delete',
   );
   return $items;
 }
diff --git a/core/modules/block/custom_block/custom_block.pages.inc b/core/modules/block/custom_block/custom_block.pages.inc
index f6c4076..77f2245 100644
--- a/core/modules/block/custom_block/custom_block.pages.inc
+++ b/core/modules/block/custom_block/custom_block.pages.inc
@@ -45,49 +45,3 @@ function custom_block_edit(CustomBlock $block) {
   return Drupal::entityManager()->getForm($block);
 }
 
-/**
- * Page callback: Form constructor for the custom block deletion form.
- *
- * @param Drupal\custom_block\Plugin\Core\Entity\CustomBlock $block
- *   The custom block to be deleted.
- *
- * @see custom_block_menu()
- * @see custom_block_delete_form_submit()
- *
- * @ingroup forms
- */
-function custom_block_delete_form($form, &$form_state, CustomBlock $block) {
-  $form_state['custom_block'] = $block;
-  $form['id'] = array(
-    '#type' => 'value',
-    '#value' => $block->id(),
-  );
-
-  $instances = $block->getInstances();
-
-  $form['message'] = array(
-    '#markup' => format_plural(count($instances), 'This will also remove 1 placed block instance.', 'This will also remove @count placed block instances.'),
-    '#access' => !empty($instances),
-  );
-
-  return confirm_form(
-    $form,
-    t('Are you sure you want to delete %label?', array('%label' => $block->label())),
-    'admin/structure/block',
-    t('This action cannot be undone.'),
-    t('Delete')
-  );
-}
-
-/**
- * Form submission handler for custom_block_delete_form().
- */
-function custom_block_delete_form_submit($form, &$form_state) {
-  $block = $form_state['custom_block'];
-  $block->delete();
-
-  drupal_set_message(t('Custom block %label has been deleted.', array('%label' => $block->label())));
-  watchdog('custom_block', 'Custom block %label has been deleted.', array('%label' => $block->label()), WATCHDOG_NOTICE);
-
-  $form_state['redirect'] = 'admin/structure/block';
-}
diff --git a/core/modules/block/custom_block/custom_block.routing.yml b/core/modules/block/custom_block/custom_block.routing.yml
index 2178d91..1d692b1 100644
--- a/core/modules/block/custom_block/custom_block.routing.yml
+++ b/core/modules/block/custom_block/custom_block.routing.yml
@@ -25,3 +25,10 @@ custom_block_type_delete:
     _entity_form: 'custom_block_type.delete'
   requirements:
     _permission: 'administer blocks'
+
+custom_block_delete:
+  pattern: '/block/{custom_block}/delete'
+  defaults:
+    _form: '\Drupal\custom_block\Form\CustomBlockDeleteForm'
+  requirements:
+    _entity_access: 'custom_block.delete'
diff --git a/core/modules/block/custom_block/lib/Drupal/custom_block/Form/CustomBlockDeleteForm.php b/core/modules/block/custom_block/lib/Drupal/custom_block/Form/CustomBlockDeleteForm.php
new file mode 100644
index 0000000..3088f45
--- /dev/null
+++ b/core/modules/block/custom_block/lib/Drupal/custom_block/Form/CustomBlockDeleteForm.php
@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\block\Form\CustomBlockDeleteForm.
+ */
+
+namespace Drupal\custom_block\Form;
+
+use Drupal\Core\Form\ConfirmFormBase;
+use Drupal\custom_block\Plugin\Core\Entity\CustomBlock;
+
+/**
+ * Provides a confirmation form for deleting a custom block entity.
+ */
+class CustomBlockDeleteForm extends ConfirmFormBase {
+
+  /**
+   * The block being deleted.
+   *
+   * @var \Drupal\custom_block\Plugin\Core\Entity\CustomBlock.
+   */
+  protected $block;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormID() {
+    return 'custom_block_delete_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getQuestion() {
+    return t('Are you sure you want to delete %name?', array('%name' => $this->block->label()));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getCancelPath() {
+    return 'admin/structure/block';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getConfirmText() {
+    return t('Delete');
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * @param \Drupal\custom_block\Plugin\Core\Entity\CustomBlock $custom_block
+   *   The custom block entity.
+   */
+  public function buildForm(array $form, array &$form_state, CustomBlock $custom_block = NULL) {
+    $this->block = $custom_block;
+    $form = parent::buildForm($form, $form_state);
+    $instances = $custom_block->getInstances();
+
+    $form['message'] = array(
+      '#type' => 'markup',
+      '#markup' => format_plural(count($instances), 'This will also remove 1 placed block instance.', 'This will also remove @count placed block instances.'),
+      '#access' => !empty($instances),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+    $this->block->delete();
+    drupal_set_message(t('Custom block %label has been deleted.', array('%label' => $this->block->label())));
+    watchdog('custom_block', 'Custom block %label has been deleted.', array('%label' => $this->block->label()), WATCHDOG_NOTICE);
+    $form_state['redirect'] = 'admin/structure/block';
+  }
+
+}