If
you have lots of information in Outlook and you want to
get all that into SharePoint, it is possible to import it
quickly by following a few steps. It is also possible with
an ICS file.
ICS is a format for calendar files that are used by various
calendars including Google Calendar, Apple iCal and Microsoft
Outlook. Calendars on websites can also use this format,
and in that case they can be downloaded to Outlook.
In this tutorial in the SharePoint Online from Scratch
series, Peter Kalmström, shows how to combine the downloading
from a website with the SharePoint connect to Outlook feature.
By doing that he can have a calendar from a website in SharePoint.
This is what Peter shows in the demo below:
How to download calendar from a website to Outlook.
How to create a new calendar in SharePoint.
How to edit links in the SharePoint Quick Launch.
How to switch calendar views in Outlook.
How to copy event from a website calendar and paste
them into a SharePoint calendar.
Note that the calendars do not synchronize. This is an import,
and if you want to update the SharePoint calendar with new
data from Outlook, you have to import again.