diff --git a/js/openseadragon_viewer.js b/js/openseadragon_viewer.js
index f6d6fb0..7883887 100644
--- a/js/openseadragon_viewer.js
+++ b/js/openseadragon_viewer.js
@@ -124,5 +124,6 @@
             });
         }
 
+        return viewer;
     };
 })(once);
diff --git a/modules/openseadragon_bookmark_url/README.md b/modules/openseadragon_bookmark_url/README.md
new file mode 100644
index 0000000..7876f96
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/README.md
@@ -0,0 +1,21 @@
+# OpenSeadragon Bookmark URL
+
+Enables the OpenSeadragon Bookmark URL plugin that tracks OpenSeadragon zoom level and coordinates to allow sharing of a display via URL.
+
+This module assumes you have added a string field to a media type that can hold the bookmark fragment, e.g.
+`file` with `field_bookmark_url`.
+
+## Requirements
+- [OpenSeadragon](https://www.drupal.org/project/openseadragon)
+
+## Installation
+
+Install as you would normally install a contributed Drupal module. For further information, see
+[Installing Drupal Modules](https://www.drupal.org/docs/extending-drupal/installing-modules).
+
+## Configuration
+Currently, no UI exists for configuration.
+
+Create an openseadragon_bookmark_url.settings.yml file and set `bookmark_url_bundle` to the media type, e.g. `file`, and `bookmark_url_field` to the field. The value from the specific media and field are inject into the Drupal settings available to javascript.
+* `bookmark_url_bundle`: `file`
+* `bookmark_url_field`: `field_bookmark_url`
diff --git a/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml b/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml
new file mode 100644
index 0000000..774f308
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml
@@ -0,0 +1,5 @@
+# Default configuration for the OpenSeadragon Bookmark URL submodule.
+# These values are intentionally empty; an administrator must choose the
+# appropriate content type and field for their site via the settings form.
+bookmark_url_bundle: ''
+bookmark_url_field: ''
diff --git a/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml b/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml
new file mode 100644
index 0000000..8cc8d2a
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml
@@ -0,0 +1,22 @@
+# Schema for openseadragon_bookmark_url.settings config object.
+
+openseadragon_bookmark_url.settings:
+  type: config_object
+  label: 'OpenSeadragon Bookmark URL settings'
+  mapping:
+    bookmark_url_bundle:
+      type: string
+      label: 'Content type (bundle) machine name'
+      constraints:
+        # Must be a valid (media) bundle machine name or empty string.
+        Regex:
+          pattern: '/^[a-z0-9_]*$/'
+          message: 'The bundle must be a valid machine name (lowercase letters, digits, and underscores only).'
+
+    bookmark_url_field:
+      type: string
+      label: 'Field machine name that stores the bookmark URL'
+      constraints:
+        Regex:
+          pattern: '/^[a-z0-9_]*$/'
+          message: 'The field name must be a valid machine name (lowercase letters, digits, and underscores only).'
diff --git a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
new file mode 100644
index 0000000..ed1986c
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
@@ -0,0 +1,42 @@
+/*jslint browser: true*/
+/*global OpenSeadragon, Drupal*/
+/**
+ * @file
+ * Attaches openseadragon-bookmark-url to OpenSeadragon viewer.
+ */
+(function($, Drupal, drupalSettings, once) {
+  'use strict';
+
+  /**
+   * The DOM element that represents the Singleton Instance of this class.
+   * @type {string}
+   */
+  var base = '#openseadragon-viewer';
+
+  /**
+   * Invoke bookmark url plugin.
+   */
+  Drupal.behaviors.openSeadragonBookmarkURL = {
+    attach: function(context, settings) {
+      Object.keys(settings.openseadragon).forEach(function(osdViewerId) {
+        // Use custom element #id if set.
+        base = '#' + osdViewerId;
+        once('openSeadragonViewerBookmarkURL', base, context).forEach(function () {
+          // Load bookmark url, but without page tracking, to allow hash to be set.
+          Drupal.openSeadragonViewer[base].bookmarkUrl({trackPage: false});
+          if (window.location.hash === '') {
+            var hash =  settings.openseadragon[osdViewerId].openseadragonBookmarkUrl;
+            if (hash !== '') {
+              window.location.hash = hash;
+            }
+          }
+          // With hash set or not, once OSD loaded, begin page tracking.
+          Drupal.openSeadragonViewer[base].addOnceHandler('open', function(){
+            Drupal.openSeadragonViewer[base].bookmarkUrl({trackPage: true});
+          });
+        });
+      });
+    }
+  };
+
+})($, Drupal, drupalSettings, once);
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml
new file mode 100644
index 0000000..98a4ddd
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml
@@ -0,0 +1,7 @@
+name: 'OpenSeadragon Bookmark URL'
+type: module
+description: 'Wrapper for https://github.com/openseadragon/bookmark-url library'
+package: Media
+core_version_requirement: ^10 || ^11
+dependencies:
+  - openseadragon:openseadragon
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
new file mode 100644
index 0000000..ce22ba3
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
@@ -0,0 +1,23 @@
+plugin:
+  remote: https://github.com/openseadragon/bookmark-url
+  version: "0.0.5"
+  license:
+    name: BSD-3-Clause
+    url: https://github.com/openseadragon/bookmark-url/blob/master/LICENSE
+    gpl-compatible: true
+  js:
+    https://cdn.jsdelivr.net/gh/openseadragon/bookmark-url@13c534c6ad7078fa44675f23185b75ee760d659c/openseadragon-bookmark-url.js:
+      type: external
+      minified: false
+      attributes:
+        integrity: "sha256-RDZWd2DzG9Asb3Pf3U0UrC0wKEGVJaC3D00Z9mqN63w="
+        crossorigin: anonymous
+openseadragon_bookmark_url:
+  js:
+    js/drupal-openseadragon-bookmark-url.js: {}
+  dependencies:
+    - core/drupal
+    - core/once
+    - core/drupalSettings
+    - openseadragon/openseadragon
+    - openseadragon_bookmark_url/plugin
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
new file mode 100644
index 0000000..cfcc1a8
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Attach bookmark-url.js.
+ */
+
+/**
+ * Attach openseadragon_bookmark_url js if openseadragon_formatter used.
+ *
+ * Implements hook_preprocess_HOOK().
+ *
+ * {@inheritDoc}
+ */
+function openseadragon_bookmark_url_preprocess_field(&$variables) {
+  if (isset($variables['items'])) {
+    foreach ($variables['items'] as $item) {
+      if (isset($item['content']['#theme']) && $item['content']['#theme'] == 'openseadragon_formatter') {
+        $variables['#attached']['library'][] = 'openseadragon_bookmark_url/openseadragon_bookmark_url';
+
+        // Inject bookmark URL into settings for later reference in js.
+        $config = \Drupal::config('openseadragon_bookmark_url.settings');
+        $bookmark_url_bundle = $config->get('bookmark_url_bundle');
+        $bookmark_url_field = $config->get('bookmark_url_field');
+        if (isset($item['content']['#entity'])) {
+          $entity = $item['content']['#entity'];
+          if ($entity->bundle() == $bookmark_url_bundle) {
+            $openseadragon_viewer_id = 'openseadragon-viewer-' . $entity->id();
+            if ($entity->hasField($bookmark_url_field)) {
+              $fragment = $entity->get($bookmark_url_field)->value;
+              $variables['#attached']['drupalSettings']['openseadragon'][$openseadragon_viewer_id]['openseadragonBookmarkUrl'] = $fragment;
+            }
+          }
+        }
+      }
+    }
+  }
+}
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml
new file mode 100644
index 0000000..6eca5c9
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml
@@ -0,0 +1,5 @@
+services:
+  openseadragon_bookmark_url.config:
+    class: Drupal\openseadragon_bookmark_url\BookmarkUrlConfig
+    arguments:
+      - '@config.factory'
diff --git a/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
new file mode 100644
index 0000000..3fbca09
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\openseadragon_bookmark_url;
+
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Config\ImmutableConfig;
+
+/**
+ * Typed accessor service for openseadragon_bookmark_url.settings.
+ *
+ * Usage (from a service or controller):
+ * @code
+ *   $config = \Drupal::service('openseadragon_bookmark_url.config');
+ *   $bundle = $config->getBundle();
+ *   $field  = $config->getField();
+ * @endcode
+ */
+final class BookmarkUrlConfig {
+
+  private const CONFIG_NAME = 'openseadragon_bookmark_url.settings';
+
+  /**
+   * The openseadragon bookmark url config.
+   *
+   * @var \Drupal\Core\Config\ImmutableConfig
+   */
+  private ImmutableConfig $config;
+
+  /**
+   * Constructs a BookmarkUrlConfig instance.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $configFactory
+   *   The Drupal config factory service.
+   */
+  public function __construct(ConfigFactoryInterface $configFactory) {
+    $this->config = $configFactory->get(self::CONFIG_NAME);
+  }
+
+  /**
+   * Returns the configured node bundle machine name, or an empty string.
+   */
+  public function getBundle(): string {
+    return $this->config->get('bookmark_url_bundle') ?? '';
+  }
+
+  /**
+   * Returns the configured field machine name, or an empty string.
+   */
+  public function getField(): string {
+    return $this->config->get('bookmark_url_field') ?? '';
+  }
+
+  /**
+   * Returns TRUE when both bundle and field have been set by an administrator.
+   */
+  public function isConfigured(): bool {
+    return $this->getBundle() !== '' && $this->getField() !== '';
+  }
+
+}