CiviCRM Community Forums (archive)

You'll want to create a custom .tpl file in your custom templates directory (not advisable to edit the CiviCRM core templates). There is a wiki page about this here: http://wiki.civicrm.org/confluence/display/CRMDOC/Customize+Built-in+and+Profile+Screens

But basically:
The file that you want to copy over to your custom templates folders is at this path:

civicrm_root/templates/CRM/Core/Calendar/Rss.tpl

So you need to create a custom templates folder (preferrably outside the civicrm directory -- making a folder in your web root is good), then you need to recreate the path by creating the following directories in that custom folder:
CRM/Core/Calendar/ and then copy the Rss.tpl file there.

Then make sure you set the custom templates path in Administer CiviCRM > Global Settings > Directories

This will have CiviCRM look for your custom template first and render that file instead.

Thank you so much for this post Emily... was very, very helpful!