The Blacktown City Medieval Fayre at Nurragingy Reserve, Doonside, will not go ahead this weekend after Sydney's heavy rain prompted concerns for safety at the event.
Blacktown City Council will refund people who had purchased tickets to the Fayre.
Council will announce new dates for the Medieval Fayre soon.
The sold-out Medieval Banquet will go ahead as planned on Saturday evening at The Colebee.
The events are part of the 50th anniversary of the Blacktown City Festival, which is offering lots of family fun this month.
Free tickets are still available for the Dorothy the Dinosaur & Friends Show on Wednesday 28 May.
Children can sing and dance with some of their favourite Wiggles characters including Dorothy, Captain Feathersword and Wags the Dog.
Streets Alive and Parade Day will deliver plenty of colour and entertainment through the Blacktown city centre on Saturday 31 May.
The Blacktown City Festival is one of the largest and longest-running in Western Sydney. A photo exhibition of the festival's history is on display at Max Webber Library, Blacktown, until the end of the month.
