The Royal Welsh Show has been cancelled due to the "deteriorating situation surrounding coronavirus".
The show's organisers said there was "no other option" after taking careful account of the latest government and public health advice.
The Royal Welsh Show, which takes place each summer at Llanelwedd near Builth Wells, was due to start on July 20th.
The Royal Welsh Agricultural Society said it had considered postponement or running a smaller event, but felt those options were not viable.
Steve Hughson, Chief Executive, said: "The Royal Welsh Agricultural Society prides itself on being a member led organisation, delivering our iconic Show and other events which are an integral part of supporting our rural communities and we understand the effect of this decision, which is made with a heavy heart.
"Whilst this news is disappointing for everyone, we are sure that you would agree that the health, safety and wellbeing of our members, visitors, exhibitors and staff is of paramount importance.
"This will be a difficult year for the Society and we understand that we are not alone and that we will all be affected by the financial outcome of this scenario."
The show's organisers say e-tickets already purchased can be rolled over to the 2021 show at no extra cost, but refunds are also available.
Full details of the cancellation policy are available via the Royal Welsh Show's website.
Coronavirus: Everything you need to know: