Site Actions -> Site Settings -> Title, description, and icon under -> Look and Feel
To change the sub-site's URL, changing the site collection URL is not so!
How to Change Site Collection URL in SharePoint?
To change the site collection's URL, There is no out-of-the-box user interface or direct ways. So, after making sure the destination URL's managed path is already in place and verifying the target site collection URL doesn't exist, I do this three step manual process.
- Backup the Source Site collection
- Delete the Source Site collection (Yes, its must! we've to delete the site collection before restoring it. Otherwise you will end up in No content databases are available for this operation GUID conflict issue.)
- Restore the Backup with the target URL
In MOSS 2007, I used to do it with
STSADM as to change site collection URL:
stsadm -o backup -url http://sharepoint.crescent.com/sites/source -overwrite -filename source.bak
stsadm -o deletesite -url http://sharepoint.crescent.com/sites/source
stsadm -o restore -url http://sharepoint.crescent.com/sites/destination -filename source.bak
Now, in SharePoint 2010 with the help of PowerShell, Why don't try placing them into a script file to save some time?
Refer to the following posts, hope it helps
Change the URL of your site using FrontPage 2002