diff --git a/components/cache/cache_pools.rst b/components/cache/cache_pools.rst
index b28788d0d64..7b77a45feea 100644
--- a/components/cache/cache_pools.rst
+++ b/components/cache/cache_pools.rst
@@ -137,9 +137,4 @@ when all items are successfully deleted)::
         # clears the "cache.validation" and "cache.app" pool
         $ php bin/console cache:pool:clear cache.validation cache.app
 
-    .. versionadded:: 3.4
-        Starting from Symfony 3.4, the ``cache:clear`` command no longer clears
-        the cache pools, so you must use the ``cache:pool:clear`` command to
-        delete them.
-
 .. _`Doctrine Cache`: https://github.com/doctrine/cache
diff --git a/components/filesystem/lock_handler.rst b/components/filesystem/lock_handler.rst
index 45ea7cda95c..4d4dcb54e4b 100644
--- a/components/filesystem/lock_handler.rst
+++ b/components/filesystem/lock_handler.rst
@@ -5,5 +5,5 @@ LockHandler
 
 .. caution::
 
-    The ``LockHandler`` utility is deprecated since Symfony 3.4. Use the new
-    Symfony Lock component instead.
+    The ``LockHandler`` utility was removed in Symfony 4.0. Use the new Symfony
+    Lock component instead.
diff --git a/form/action_method.rst b/form/action_method.rst
index 132d766ea4b..b044420f28a 100644
--- a/form/action_method.rst
+++ b/form/action_method.rst
@@ -126,8 +126,6 @@ to the ``form()`` or the ``form_start()`` helper functions:
 
         <!-- templates/default/new.html.php -->
         <?php echo $view['form']->start($form, array(
-            // The path() method was introduced in Symfony 2.8. Prior to 2.8,
-            // you had to use generate().
             'action' => $view['router']->path('target_route'),
             'method' => 'GET',
         )) ?>
diff --git a/reference/configuration/framework.rst b/reference/configuration/framework.rst
index 7c5721870c3..92c59e15b5c 100644
--- a/reference/configuration/framework.rst
+++ b/reference/configuration/framework.rst
@@ -1860,9 +1860,6 @@ The cache clearer used to clear your PSR-6 cache.
 prefix_seed
 ...........
 
-.. versionadded:: 3.2
-    The ``prefix_seed`` option was introduced in Symfony 3.2.
-
 **type**: ``string`` **default**: ``null``
 
 If defined, this value is used as part of the "namespace" generated for the
diff --git a/reference/configuration/security.rst b/reference/configuration/security.rst
index a945fe3700a..41f47b1749a 100644
--- a/reference/configuration/security.rst
+++ b/reference/configuration/security.rst
@@ -219,7 +219,6 @@ Each part will be explained in the next section.
 
                         # by default, a session must exist before submitting an authentication request
                         # if false, then Request::hasPreviousSession is not called during authentication
-                        # new in Symfony 2.3
                         require_previous_session: true
 
                         service:      ~
diff --git a/reference/forms/types/options/choice_value.rst.inc b/reference/forms/types/options/choice_value.rst.inc
index 66ecf558994..f06844c0f6a 100644
--- a/reference/forms/types/options/choice_value.rst.inc
+++ b/reference/forms/types/options/choice_value.rst.inc
@@ -20,11 +20,3 @@ for each choice or ``null`` in some cases, which you need to handle:
     'choice_value' => function (MyOptionEntity $entity = null) {
         return $entity ? $entity->getId() : '';
     },
-
-.. caution::
-
-    In Symfony 2.7, there was a small backwards-compatibility break with how the
-    ``value`` attribute of options is generated. This is not a problem unless you
-    rely on the option values in JavaScript. See `issue #14825`_ for details.
-
-.. _`issue #14825`: https://github.com/symfony/symfony/pull/14825
diff --git a/security/host_restriction.rst b/security/host_restriction.rst
index c10de8bc2dc..0a07e4f6262 100644
--- a/security/host_restriction.rst
+++ b/security/host_restriction.rst
@@ -1,6 +1,5 @@
 How to Restrict Firewalls to a Specific Host
 ============================================
 
-As of Symfony 2.5, more possibilities to restrict firewalls have been added. 
-You can read everything about all the possibilities (including ``host``) 
-in ":doc:`/security/firewall_restriction`".
+There are more possibilities to restrict firewalls. You can read everything
+about all the possibilities (including ``host``)  in ":doc:`/security/firewall_restriction`".