Remove Domain (Classic Site)

Even though you cannot edit the old site, you may be able to remove the domain from it.

1. Go to Classic Sites page https://sites.google.com/site/

2. Select the site

3. Click More Actions

4. Select Manage site.

5. Click Web Address in the left  column.

6. Click to delete the domain link.

Has the site been deleted?

https://sites.google.com/site/sites/system/app/pages/meta/dashboard/deleted 

If so you should be able to restore it and remove the domain.

Alternatively you can permanently delete it and the domain should be released within a day or so. My recommendation is to restore and remove.

Thanks Perjury!