T he age-pocked walls of the Venice Conservatory courtyard rise to a brilliant sky. Around us swells the raw sound of the singer Celeste’s voice and the deep thrum of African instruments. The experience is visceral.

Beautiful. And slightly surreal, as the Hollywood actor Bill Murray has just given me a straw hat. We are gathered for the opening of an extraordinary three-day micro-festival, a debut event thrown by specialist organisers Littlegig in collaboration with Homo Faber (the Richemont-backed organisation that celebrates contemporary craftsmanship).

It is part of a rise in tiny, often secretive or invitation-only gatherings — like Earth One, where this year leaders gathered on a boat to cross the Atlantic and forge alliances around climate change; Mistress Mary, the invitation-only little sister of the Secret Garden Party; or Ondalinda, a health and art-themed members festival held in places including Mexico and Montenegro, for which rock stars and actors jostle to apply. None of these is a normal festival — and each is invitation only. For those who attend, the richness is about the combined experiences of a specialised group and forging a fresh community.

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