The delete command removes all of the calendar information from the calendar database and cannot be undone. After you delete a calendar, you can recover the calendar data only if it was backed up. For more information, see Chapter 17, Backing Up and Restoring Calendar Server Data.
The cscal utility lets you delete a single calendar or multiple calendars.
For example, to delete a specific calendar with the calendar ID jsmith:meetings:
cscal delete jsmith:meetings
To delete all calendars whose primary owner is jsmith:
cscal -o jsmith delete