diff --git a/tests/features/joinup_core/persistent_uris.feature b/tests/features/joinup_core/persistent_uris.feature
index 7bea4309d2..8384eca5c4 100644
--- a/tests/features/joinup_core/persistent_uris.feature
+++ b/tests/features/joinup_core/persistent_uris.feature
@@ -45,7 +45,7 @@ Feature:
 
     And "eira" terms:
       | tid                                   | name         | description                                |
-      | http://data.europa.eu/dr8/DreamDomain | Dream Domain | You're safe from pain in the dream domain. |
+      | http://data.europa.eu/dr8/Dream/Domain | Dream Domain | You're safe from pain in the dream domain. |
 
     And discussion content:
       | title                 | body                  | collection            | state     |
@@ -103,34 +103,23 @@ Feature:
 
     # Our semantic content has a persistent canonical path at Europe's
     # official data portal: "http://data.europa.eu/w21/{uuid}". The data portal
-    # links back to the Joinup servers. In order to resolve the UUIDs we employ
-    # the intermediate path '/data/{uuid}' which will forward the request to the
-    # actual page that contains the content in human digestible format.
-    Given I am on "data/ffb0ffc9-7704-45d3-95b3-42706b6320e5"
-    Then I should see the heading "Persistent solution"
-    And I am on "data/w21/ffb0ffc9-7704-45d3-95b3-42706b6320e5"
+    # links back to the Joinup servers.
+    Given I am on "data/w21/ffb0ffc9-7704-45d3-95b3-42706b6320e5"
     Then I should see the heading "Persistent solution"
 
-    Given I am on "data/37b8103e-26e5-4c81-8ce5-43ced02ff7d0"
-    Then I should see the heading "Persistent collection"
-    And I am on "data/w21/37b8103e-26e5-4c81-8ce5-43ced02ff7d0"
+    Given I am on "data/w21/37b8103e-26e5-4c81-8ce5-43ced02ff7d0"
     Then I should see the heading "Persistent collection"
 
-    Given I am on "data/98004ec9-62f3-4734-a1b6-af7e4838b09c"
-    Then I should see the heading "Persistent release 23"
-    And I am on "data/w21/98004ec9-62f3-4734-a1b6-af7e4838b09c"
+    Given I am on "data/w21/98004ec9-62f3-4734-a1b6-af7e4838b09c"
     Then I should see the heading "Persistent release 23"
 
-    Given I am on "data/643a2a52-da3b-4594-92bb-295d8134e1fb"
-    Then I should see the heading "Persistent distribution"
-    And I am on "data/w21/643a2a52-da3b-4594-92bb-295d8134e1fb"
+    Given I am on "data/w21/643a2a52-da3b-4594-92bb-295d8134e1fb"
     Then I should see the heading "Persistent distribution"
 
-    Given I am on "data/4205229d-92b6-4cac-80af-d8c2296d923c"
-    Then I should see the heading "Persistent licence"
-    And I am on "data/w21/4205229d-92b6-4cac-80af-d8c2296d923c"
+    Given I am on "data/w21/4205229d-92b6-4cac-80af-d8c2296d923c"
     Then I should see the heading "Persistent licence"
 
-    Given I am on "data/dr8/DreamDomain"
+    Given I am on "data/dr8/Dream/Domain"
     Then I should see the heading "Dream Domain"
     And I should see "You're safe from pain in the dream domain."
+    And the url should match "/taxonomy/term/http_e_f_fdata_ceuropa_ceu_fdr8_fDream_fDomain"
diff --git a/web/modules/custom/joinup_core/joinup_core.routing.yml b/web/modules/custom/joinup_core/joinup_core.routing.yml
index 448f032fd6..8a1bf7da31 100644
--- a/web/modules/custom/joinup_core/joinup_core.routing.yml
+++ b/web/modules/custom/joinup_core/joinup_core.routing.yml
@@ -14,21 +14,17 @@ joinup_core.file_field_info:
   requirements:
       _permission: 'administer content types'
 
-# @todo Remove this when the w21 redirect has been updated.
-joinup_core.id_redirect.deprecated:
-  path: '/data/{uuid}'
-  defaults:
-    _controller: '\Drupal\joinup_core\Controller\IdRedirect::redirectToRdfEntity'
-    namespace: w21
-  requirements:
-    _access: 'TRUE'
-
 joinup_core.id_redirect:
   path: '/data/{namespace}/{uuid}'
   defaults:
     _controller: '\Drupal\joinup_core\Controller\IdRedirect::redirectToRdfEntity'
   requirements:
     _access: 'TRUE'
+    # Even though we are using a custom processor to alter the UUID value to not
+    # include the /, we need to set the value of UUID to match '.+' because the
+    # Drupal routing system uses by default the '[^/]' for route parameters.
+    # @see \Drupal\Core\Routing\Router::doMatchCollection()
+    uuid: '.+'
 
 joinup_core.rdf_entity_uri_web_converter_page:
   path: '/rdf'
diff --git a/web/modules/custom/joinup_core/joinup_core.services.yml b/web/modules/custom/joinup_core/joinup_core.services.yml
index ff9a5e23df..a49001027b 100644
--- a/web/modules/custom/joinup_core/joinup_core.services.yml
+++ b/web/modules/custom/joinup_core/joinup_core.services.yml
@@ -1,12 +1,16 @@
 services:
+
   joinup_core.joinup_version:
     class: Drupal\joinup_core\JoinupVersion
+
   logger.channel.joinup_core:
     parent: logger.channel_base
     arguments: ['joinup_core']
+
   joinup_core.requirements_helper:
     class: Drupal\joinup_core\RequirementsHelper
     arguments: ['@database']
+
   joinup_core.local_task_links_helper:
     class: Drupal\joinup_core\LocalTaskLinksHelper
     arguments: ['@entity_type.manager']
@@ -15,3 +19,8 @@ services:
     arguments: ['@entity_field.manager']
     tags:
       - { name: event_subscriber }
+
+  path_processor.joinup_core:
+    class: Drupal\joinup_core\PathProcessor\IdRedirectUuidProcessor
+    tags:
+      - { name: path_processor_inbound, priority: 200 }
diff --git a/web/modules/custom/joinup_core/src/Controller/IdRedirect.php b/web/modules/custom/joinup_core/src/Controller/IdRedirect.php
index 0468b5a49e..8c86c91bcf 100644
--- a/web/modules/custom/joinup_core/src/Controller/IdRedirect.php
+++ b/web/modules/custom/joinup_core/src/Controller/IdRedirect.php
@@ -28,6 +28,9 @@ public function redirectToRdfEntity(string $namespace, string $uuid): RedirectRe
       return $this->redirect('joinup_core.not_found', [], [], 404);
     }
 
+    // The UUID has been encoded early to allow slashes.
+    // @see \Drupal\joinup_core\PathProcessor\IdRedirectNamespaceProcessor::processInbound()
+    $uuid = urldecode($uuid);
     return $this->redirect("entity.$entity_type_id.canonical", [
       $entity_type_id => "http://data.europa.eu/$namespace/$uuid",
     ], [], 301);
diff --git a/web/modules/custom/joinup_core/src/PathProcessor/IdRedirectUuidProcessor.php b/web/modules/custom/joinup_core/src/PathProcessor/IdRedirectUuidProcessor.php
new file mode 100644
index 0000000000..f5f34a7557
--- /dev/null
+++ b/web/modules/custom/joinup_core/src/PathProcessor/IdRedirectUuidProcessor.php
@@ -0,0 +1,38 @@
+<?php
+
+declare (strict_types = 1);
+
+namespace Drupal\joinup_core\PathProcessor;
+
+use Drupal\Core\PathProcessor\InboundPathProcessorInterface;
+use Drupal\joinup_core\Controller\IdRedirect;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Handles joinup_core.id_redirect route case when {uuid} param contains a '/'.
+ *
+ * Because the joinup_core.id_redirect route's {uuid} parameter may contain one
+ * or more slashes, we encode the URL parameter as Drupal doesn't allow slashes
+ * in parameters, as opposed to Symfony. We revert the parameter encoding,
+ * later, in IdRedirect::redirectToRdfEntity().
+ *
+ * @see https://www.drupal.org/project/drupal/issues/2741939
+ * @see https://symfony.com/doc/3.4/routing/slash_in_parameter.html
+ * @see \Drupal\joinup_core\Controller\IdRedirect::redirectToRdfEntity()
+ */
+class IdRedirectUuidProcessor implements InboundPathProcessorInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processInbound($path, Request $request): string {
+    if (strpos($path, '/data/') === 0 && !$request->query->has('uuid')) {
+      preg_match('#^/data/(?<namespace>[^/]+)/(?<uuid>.+)$#', $path, $matches);
+      if (!empty($matches['namespace']) && !empty($matches['uuid'][0]) && IdRedirect::getEntityTypeFromPersistentUriNamespace($matches['namespace'])) {
+        return '/data/' . $matches['namespace'] . '/' . urlencode($matches['uuid']);
+      }
+    }
+    return $path;
+  }
+
+}