Hello,
I'm not sure that you were informed about this script that could interest other organizations and events creator.
Last year, 0x010C coded a calendar in lua [1][2] for Wikimédia France.
Features: ical, filter by tag and location, 3 display mode (but map doesn't seem to work), interface in different languages.
[1] https://meta.wikimedia.org/wiki/Module:Events_calendar [2] https://meta.wikimedia.org/wiki/Events_calendar/about
Pyb