Boardmasters festival in Newquay has been cancelled the night before gates were set to open.
It follows concerns over warnings of strong winds and heavy rain for the end of the week.
The four-day music and surfing event at Fistral Beach and Watergate Bay was set to open to guests on Wednesday (7 August) with entertainment starting on Friday.
The surfing event is still expected to take place.
In a statement issued on Tuesday night, organisers said "the potential risk is too severe for the event to go ahead."
This year's festival was set to be headlined by Wu-Tang Clan, Florence & The Machine, and Foals - who tweeted they were "gutted" about the cancellation.
Speaking to ITV News the day after the event was cancelled, Boardmasters Event Organiser Andrew Topham reiterated information would become available on the festival's social media channels as website "as soon as possible."
Boardmasters has since confirmed that all eligible tickets will be refunded within three weeks.
Those travelling to the festival by train have been advised that return tickets from Newquay between today and Monday can be used from 9:30am this morning.
Coach journeys to the festival site have also faced disruption.
Those due to visit the festival have expressed anger and shock on social media at the decision.
Dave Arberry from Bristol tweeted a summary of his spending on the festival so far:
The festival has been disrupted by bad weather in the past, with downpours throughout last year's festival.
In 2014, the final day of music was cancelled due to poor conditions.