Google Apps Manager (GAM) – delete all user calendar events
If you need to delete all the events from a Google calendar you can do the following.
First, you need to have the Calendar ID email address (this is not the user’s email). It can be found in the calendar settings.
Example:
(Calendar ID: domain.com_33393638303931322d323231@resource.calendar.google.com)
Command:
gam calendar <calendar email> wipe events
gam calendar domain.com_33393638303931322d323231@resource.calendar.google.com wipe events