Command-line tool to make local backups of your Google Calendar (or any other calendar).
You need a machine which is able to run Windows PowerShell.
Change the values in the config file as follows:
The calendar files will be downloaded to this folder
Valid values are:
0: The downloaded files will be overwritten on each run
1: On each run, the files will be saved in a new subfolder with the current date/time. The old files will never be deleted.
Multiple items possible. Each one needs:
url: The calendar's download URL
filename: The downloaded calendar will be saved with this filename
(note: if you use the same name multiple times, the second file will overwrite the first!)
I wrote this tool to download my Google Calendar, so I only know the answer for Google:
Each Google Calendar has a private address, which is a direct link to the calendar in the ICalendar format.
Here are the instructions how to get the private address.
Google Calendar Backup is licensed under the MIT License.