src/Routing/Routes.php                | 50 ++++++++++++++++++-----------------
 tests/src/Unit/Routing/RoutesTest.php | 16 +++++------
 2 files changed, 34 insertions(+), 32 deletions(-)

diff --git a/src/Routing/Routes.php b/src/Routing/Routes.php
index e05a05a..bc5f6e2 100644
--- a/src/Routing/Routes.php
+++ b/src/Routing/Routes.php
@@ -204,8 +204,8 @@ class Routes implements ContainerInjectionInterface {
     if ($resource_type->isLocatable()) {
       $individual_route = new Route("/{$path}/{{$entity_type_id}}");
       $individual_route->setMethods(['GET']);
-      // No _entity_access requirement because "view" and "view label" access are
-      // checked in the controller. So it's safe to allow anybody access.
+      // No _entity_access requirement because "view" and "view label" access
+      // are checked in the controller. So it's safe to allow anybody access.
       $individual_route->setRequirement('_access', 'TRUE');
       $routes->add(static::getRouteName($resource_type, 'individual'), $individual_route);
     }
@@ -230,28 +230,30 @@ class Routes implements ContainerInjectionInterface {
       $routes->add(static::getRouteName($resource_type, 'individual.delete'), $individual_remove_route);
     }
 
-    // Get an individual resource's related resources.
-    $related_route = new Route("/{$path}/{{$entity_type_id}}/{related}");
-    $related_route->setMethods(['GET']);
-    // @todo: remove this when each related route is defined per relationship field and access is no longer checked by the controller in https://www.drupal.org/project/jsonapi/issues/2953346.
-    $related_route->setRequirement('_access', 'TRUE');
-    $routes->add(static::getRouteName($resource_type, 'related'), $related_route);
-
-    // Read, update, add, or remove an individual resources relationships to
-    // other resources.
-    $relationship_route = new Route("/{$path}/{{$entity_type_id}}/relationships/{related}");
-    $relationship_route->setMethods($resource_type->isMutable()
-      ? ['GET', 'POST', 'PATCH', 'DELETE']
-      : ['GET']
-    );
-    // @todo: remove the _on_relationship default in https://www.drupal.org/project/jsonapi/issues/2953346.
-    $relationship_route->addDefaults(['_on_relationship' => TRUE]);
-    $relationship_route->addDefaults(['serialization_class' => Relationship::class]);
-    $relationship_route->setRequirement('_csrf_request_header_token', 'TRUE');
-    $routes->add(static::getRouteName($resource_type, 'relationship'), $relationship_route);
-
-    // Add entity parameter conversion to every route.
-    $routes->addOptions(['parameters' => [$entity_type_id => ['type' => 'entity:' . $entity_type_id]]]);
+    if ($resource_type->isLocatable()) {
+      // Get an individual resource's related resources.
+      $related_route = new Route("/{$path}/{{$entity_type_id}}/{related}");
+      $related_route->setMethods(['GET']);
+      // @todo: remove this when each related route is defined per relationship field and access is no longer checked by the controller in https://www.drupal.org/project/jsonapi/issues/2953346.
+      $related_route->setRequirement('_access', 'TRUE');
+      $routes->add(static::getRouteName($resource_type, 'related'), $related_route);
+
+      // Read, update, add, or remove an individual resources relationships to
+      // other resources.
+      $relationship_route = new Route("/{$path}/{{$entity_type_id}}/relationships/{related}");
+      $relationship_route->setMethods($resource_type->isMutable()
+        ? ['GET', 'POST', 'PATCH', 'DELETE']
+        : ['GET']
+      );
+      // @todo: remove the _on_relationship default in https://www.drupal.org/project/jsonapi/issues/2953346.
+      $relationship_route->addDefaults(['_on_relationship' => TRUE]);
+      $relationship_route->addDefaults(['serialization_class' => Relationship::class]);
+      $relationship_route->setRequirement('_csrf_request_header_token', 'TRUE');
+      $routes->add(static::getRouteName($resource_type, 'relationship'), $relationship_route);
+
+      // Add entity parameter conversion to every route.
+      $routes->addOptions(['parameters' => [$entity_type_id => ['type' => 'entity:' . $entity_type_id]]]);
+    }
 
     return $routes;
   }
diff --git a/tests/src/Unit/Routing/RoutesTest.php b/tests/src/Unit/Routing/RoutesTest.php
index c31a68d..e0537a6 100644
--- a/tests/src/Unit/Routing/RoutesTest.php
+++ b/tests/src/Unit/Routing/RoutesTest.php
@@ -79,14 +79,6 @@ class RoutesTest extends UnitTestCase {
     $this->assertSame('entity_type_1--bundle_1_1', $route->getDefault(Routes::RESOURCE_TYPE_KEY));
     $this->assertEquals(['GET'], $route->getMethods());
     $this->assertSame(Routes::FRONT_CONTROLLER, $route->getDefault(RouteObjectInterface::CONTROLLER_NAME));
-    // Check the collection POST route.
-    $route = $iterator->offsetGet('jsonapi.entity_type_1--bundle_1_1.collection.post');
-    $this->assertSame('/jsonapi/entity_type_1/bundle_1_1', $route->getPath());
-    $this->assertSame(['lorem', 'ipsum'], $route->getOption('_auth'));
-    $this->assertSame('entity_type_1--bundle_1_1', $route->getDefault(Routes::RESOURCE_TYPE_KEY));
-    $this->assertEquals(['POST'], $route->getMethods());
-    $this->assertSame(Routes::FRONT_CONTROLLER, $route->getDefault(RouteObjectInterface::CONTROLLER_NAME));
-    $this->assertSame('Drupal\jsonapi\JsonApiResource\JsonApiDocumentTopLevel', $route->getDefault('serialization_class'));
   }
 
   /**
@@ -109,6 +101,14 @@ class RoutesTest extends UnitTestCase {
       'resource_type' => ['type' => 'jsonapi_resource_type'],
     ], $route->getOption('parameters'));
 
+    $route = $iterator->offsetGet('jsonapi.entity_type_1--bundle_1_1.individual.create');
+    $this->assertSame('/jsonapi/entity_type_1/bundle_1_1', $route->getPath());
+    $this->assertSame(['lorem', 'ipsum'], $route->getOption('_auth'));
+    $this->assertSame('entity_type_1--bundle_1_1', $route->getDefault(Routes::RESOURCE_TYPE_KEY));
+    $this->assertEquals(['POST'], $route->getMethods());
+    $this->assertSame(Routes::FRONT_CONTROLLER, $route->getDefault(RouteObjectInterface::CONTROLLER_NAME));
+    $this->assertSame(JsonApiDocumentTopLevel::class, $route->getDefault('serialization_class'));
+
     $route = $iterator->offsetGet('jsonapi.entity_type_1--bundle_1_1.individual.patch');
     $this->assertSame('/jsonapi/entity_type_1/bundle_1_1/{entity_type_1}', $route->getPath());
     $this->assertSame('entity_type_1--bundle_1_1', $route->getDefault(Routes::RESOURCE_TYPE_KEY));