Make Google Calendar public and Calendar ID
January 26, 2017
Eventon Sync addon can fetch events from any public Google Calendar. The Google API key you created will only allow you to read from public calendars. Adding a google calendar that is not public will not fetch events from google calendar to eventon.
You can make a Google calendar public by following these steps:
Open google calendar and go to calendar settings.
Select the calendars tab and select the calendar you want to make public for fetching events using sync addon
Go to Share this Calendar tab and check the option that allow for public calendar
There you have it, that will make the calendar public.
NOTE: Keep in mind by making a google calendar public, the calendar can be reached also from google or by whomever have the calendar ID or a link to your calendar on Google.
Under the calendar settings > Select a calendar of your choice. Then go to Calendar Details tab and under Calendar Address you will find the calendar ID for your google calendar. Which is a email address with @group.calendar.google.com
IMPORTANT: The google calendar have to be shared with at least one email address the google calendar to generate this full calendar ID otherwise the calendar ID will NOT work. (Credit to @nathankirkham1990)