# How can I set up canonical tags?
> Two worked examples: a self-referencing canonical tag, and a Shared Field group that lets editors point a page at an alternative canonical URL.
URL: https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/seo/set-up-canonical-tags.html
category: Developing in Cascade
article-type: how-to
content-kind: faq
release-availability: all
tags: templates, data-definitions, velocity
updated: 2026-10-06
This article gives two sample methods for configuring canonical tags. They're examples, and may need additional development depending on your needs.
## Self-referencing canonical tags
1. Create a Velocity [Format](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/script-formats/index.html) containing:
```velocity
```
1. Create a system-region within the `` tags of your Template:
```html
<system-region name="CANONICAL" />
```
1. Attach the Format to the `CANONICAL` region, at the Template, Configuration, or Page level.
1. Visit **Manage Site > Site Settings** and change **Link Rewriting** to **Absolute**.
1. Publish your pages.
> For a single page or a few pages, attach the Format at the page level and set that page's link rewriting under **Edit > Configure > Override the current Site's asset link rewriting behavior for this asset**.
## Adding an alternative canonical URL option
This example lets a page output a self-referencing canonical tag or point at another page instead.
1. Create a system-region within the `` tags of your Template:
```html
<system-region name="CANONICAL" />
```
1. Create a [Shared Field](https://www.hannonhill.com/cascadecms/latest/articles/design-in-cascade/data-definitions/shared-fields.html) group with this XML:
```xml
<system-data-structure>
```
1. Add this Shared Field group to the top of one or more existing Data Definitions.
1. Create a Velocity [Format](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/script-formats/index.html) containing:
```velocity
#set ($canonical = $currentPage.getStructuredDataNode("canonical"))
#if (!$canonical.getChild("canonical-alternate").hasTextValue("yes"))
## use current page's URL
#set ($href = $currentPage.link)
#else
## use alternate canonical page URL
#if ($canonical.getChild("canonical-url-type").hasTextValue("page"))
#set ($href = $canonical.getChild("page").asset.link)
#elseif ($canonical.getChild("canonical-url-type").hasTextValue("url"))
#set ($href = $canonical.getChild("url").textValue)
#end
#end
## output the canonical tag
```
1. Attach this Format to the `CANONICAL` region.
1. Visit **Manage Site > Site Settings** and change **Link Rewriting** to **Absolute**.
1. Edit one or more pages, configure the canonical options, and publish.
> Only users in the `Administrators` group see these options, because of the `restrict-to-groups="Administrators"` attribute on the field group. Remove or adjust that attribute for your own groups.