If you are looking for a privacy-friendly alternative to Facebook Events, you might want to check out Mobilizon:
It's a free open source federated events platform, and is part of the Fediverse as it uses the ActivityPub protocol.
Because it's still new, it currently only federates between Mobilizon instances. You can't follow Mobilizon instances from Mastodon yet, however this is planned for the future.
Discover & explore Mastodon with no ads and no surveillance. Publish anything you want on Mastodon: links, pictures, text, audio & video.
All on a platform that is community-owned and ad-free.
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