Looking for advice on Company Calendar Setup

[Chris Campanile]

Looking for advice on best way to setup company wide calendar. This would mainly be to show holidays and users would automatically see these calendar events preferably on their individual calendars.
We have 2 physical teams: US and Offshore. Would be nice if we could have US Holidays showing to Offshore as optional (as in they're notified) and Offshore holidays having US folks as optional (so they're just notified too). We have a Companywide Team, where everyone is automatically added, and I suspect I could add a calendar to that somehow, but wouldn't be getting the delineation between the 2 physical groups of people.
Can you please help me understand what the best setup for this would be, using Outlook, Teams, Groups/DLs, and/or Sharepoint?
We don't use it, but is this where Yammer fits in?

[#2]

There's no perfect solutions for this, even less so when you want to target different groups. The usual options are SharePoint calendar (poor Outlook integration), public folder calendar (no mobile access), shared mailbox calendar (can get it on a mobile, but only on the Outlook app). Groups-based calendar (the permission model can be a problem, cannot publish the calendar/make it accessible as a web page). Teams doesn't have anything to offer on that front, until they release the calendar improvements at least, but can be used to add a tab with the calendar.