Organisers are hoping this year's Protecta Insurance River City Park Up builds on the success of 2017's inaugural event.
Wanganui City College grounds will become a sea of cars from 10am this Sunday for the annual event which the Wanganui Road Rodders debuted in 2017.
"We're really looking forward to it and the weather's going to be good," organiser Grant Rivers said.
More than 500 vehicles attended last year's park up and Mr Rivers hoped there would be more for the second edition with vehicles of various types coming from across the North Island.
The River City Park Up also includes food stalls, face painting and trade displays.
"There's lots for people to see and do and have a go at. It brings a lot of people to town."
Last year's event raised about $4500 for charity and this year proceeds will go to Riding for the Disabled, Surf Lifesaving and the Coastguard.
The Road Rodders began hosting the event after a similar biennial event run by Rotary ended.
Entry is a gold coin donation with vehicle owners paying $5 to display.
All proceeds this year will go to Riding for the Disabled, Surf Lifesaving and the Coastguard.