mastodon.world is one of the many independent Mastodon servers you can use to participate in the fediverse.
Generic Mastodon server for anyone to use.

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active users

Backpack and Snorkel

Founded in 1592 by Queen Elizabeth I and modelled after the universities of Oxford and Cambridge, Trinity College is Ireland's oldest university. You can visit the campus grounds and it is worth it! backpackandsnorkel.com/Ireland