The Bowral Classic kicked fundraising efforts into gear on Sunday.
The annual event raised more than $100,000 as of Sunday afternoon, with participants raising money for charities of their choice.
Riders took part in one of four routes including a 175km maxi classic, a 120km challenge classic, a 90km classic and a 35km social classic.
The event started at 6.30am on Bong Bong Street in Bowral and finished with a victory lap on the velodrome at Eridge Park.
The cycling series has raised more than $300,000 for various charities since the inaugural event in 2016.
The event's charity partners include the National Breast Cancer Foundation, the Black Dog Institute, Freedom Wheels, JDRF for type one diabetes research, Chris O'Brien Lifehouse, Make-A-Wish and Rare Cancers Australia.
One of the aims of the event is to showcase the scenic roads and diverse terrain of the Southern Highlands.
The Classic also provides an economic benefit for Highlands businesses, with increased visitation to shops, restaurants, cafes and wineries.
Event participants ranged from competitive riders to families, friends and social riders.
The winners of each race will be confirmed by Monday morning.