Spectators lined the Avon River to watch the start of the 2018 Avon Descent.

Power boats left Northam at 8am on Saturday 4 August, followed by the paddlers at 8.30am. 

Day two will leave from Cobblers Pool before trophy presentations at Riverside Gardens on Sunday afternoon.

The challenge of the Avon came about when a Northam resident decided to test a fossil fuel substitute on a Honda Outboard motor on the back of an Aluminium boat with his mates in a journey from Northam to Perth. 

This event was first held in 1973 with just 49 competitors, no rules, no officials and no checkpoints.

In the past 45 years, over 31,000 people have competed in the Avon Descent, from novices and families, to World and Olympic Champions.