diff --git a/core/INSTALL.txt b/core/INSTALL.txt
index c839761..74ceed9 100644
--- a/core/INSTALL.txt
+++ b/core/INSTALL.txt
@@ -353,7 +353,7 @@ Never edit Drupal's core modules and themes; instead, use the hooks available in
 the Drupal API. To modify the behavior of Drupal, develop a module as described
 at https://www.drupal.org/developing/modules. To modify the look of Drupal,
 create a subtheme as described at https://www.drupal.org/node/2165673, or a
-completely new theme as described at https://www.drupal.org/documentation/theme
+completely new theme as described at https://www.drupal.org/docs/8/theming
 
 MULTISITE CONFIGURATION
 -----------------------
diff --git a/core/core.api.php b/core/core.api.php
index 68f4636..07f90c0 100644
--- a/core/core.api.php
+++ b/core/core.api.php
@@ -1272,7 +1272,7 @@
  *   site; CSS files, which alter the styling applied to the HTML; and
  *   JavaScript, Flash, images, and other files. For more information, see the
  *   @link theme_render Theme system and render API topic @endlink and
- *   https://www.drupal.org/theme-guide/8
+ *   https://www.drupal.org/docs/8/theming
  * - Modules: Modules add to or alter the behavior and functionality of Drupal,
  *   by using one or more of the methods listed below. For more information
  *   about creating modules, see https://www.drupal.org/developing/modules/8
diff --git a/core/lib/Drupal/Core/Render/theme.api.php b/core/lib/Drupal/Core/Render/theme.api.php
index 2970b27..f9d3684 100644
--- a/core/lib/Drupal/Core/Render/theme.api.php
+++ b/core/lib/Drupal/Core/Render/theme.api.php
@@ -31,7 +31,7 @@
  * 8 themes.
  *
  * For further information on theming in Drupal 8 see
- * https://www.drupal.org/theme-guide/8
+ * https://www.drupal.org/docs/8/theming
  *
  * For further Twig documentation see
  * http://twig.sensiolabs.org/doc/templates.html
@@ -223,7 +223,7 @@
  * same, which gives users fewer user interface patterns to learn.
  *
  * For further information on the Theme and Render APIs, see:
- * - https://www.drupal.org/documentation/theme
+ * - https://www.drupal.org/docs/8/theming
  * - https://www.drupal.org/developing/api/8/render
  * - https://www.drupal.org/node/722174
  * - https://www.drupal.org/node/933976
diff --git a/core/themes/classy/README.txt b/core/themes/classy/README.txt
index a518123..52bf17a 100644
--- a/core/themes/classy/README.txt
+++ b/core/themes/classy/README.txt
@@ -8,10 +8,11 @@ To use Classy as your base theme, set the 'base theme' in your theme's .info.yml
 file to "classy":
   base theme: classy
 
-See https://www.drupal.org/theme-guide/8/classy for more information on using
-the Classy theme.
+See https://www.drupal.org/docs/8/theming-drupal-8/using-classy-as-a-base-theme
+for more information on using the Classy theme.
 
 ABOUT DRUPAL THEMING
 --------------------
 
-See https://www.drupal.org/theme-guide/8 for more information on Drupal theming.
+See https://www.drupal.org/docs/8/theming for more information on Drupal
+theming.
diff --git a/core/themes/classy/classy.info.yml b/core/themes/classy/classy.info.yml
index 34b07b5..05ef0d7 100644
--- a/core/themes/classy/classy.info.yml
+++ b/core/themes/classy/classy.info.yml
@@ -1,6 +1,6 @@
 name: Classy
 type: theme
-description: 'A base theme with sensible default CSS classes added. Learn how to use Classy as a base theme in the <a href="https://www.drupal.org/theme-guide/8">Drupal 8 Theming Guide</a>.'
+description: 'A base theme with sensible default CSS classes added. Learn how to use Classy as a base theme in the <a href="https://www.drupal.org/docs/8/theming">Drupal 8 Theming Guide</a>.'
 package: Core
 version: VERSION
 core: 8.x
diff --git a/core/themes/stable/README.txt b/core/themes/stable/README.txt
index a8687a0..0539730 100644
--- a/core/themes/stable/README.txt
+++ b/core/themes/stable/README.txt
@@ -23,4 +23,4 @@ ABOUT DRUPAL THEMING
 --------------------
 
 For more information, see Drupal.org's theming guide.
-https://www.drupal.org/theme-guide/8
+https://www.drupal.org/docs/8/theming
diff --git a/core/themes/stark/README.txt b/core/themes/stark/README.txt
index 552261a..62bf058 100644
--- a/core/themes/stark/README.txt
+++ b/core/themes/stark/README.txt
@@ -17,7 +17,7 @@ ABOUT DRUPAL THEMING
 --------------------
 
 To learn how to build your own custom theme and override Drupal's default code,
-see the Theming Guide: https://www.drupal.org/theme-guide
+see the Theming Guide: https://www.drupal.org/docs/8/theming
 
 See the themes/README.txt for more information on where to place your
 custom themes to ensure easy maintenance and upgrades.