Thousands of spectators are gathering in Salford Quays for the annual Triathlon World Cup.
The triathletes will compete in the gruelling event which features a 1500m swim, 40km cycle and 10km run.
As well as a prize fund there is the chance for winners to gain selection for the World Championships in Hamburg.
A team from Emmerdale, including Matthew Wolfenden who plays David Metcalfe in the soap, will compete in the relay event.
Tim Don is favourite to deliver a home win at the event after becoming world champion last year.
Councillor John Merry, leader of Salford City Council, said: "Salford Quays has established itself as a world class sporting venue, and we are delighted that the BG Triathlon World Cup is returning for the fifth time to the city.
"Last year the event attracted 22,000 spectators to the Quays to enjoy the fantastic free sporting occasion.
"We look forward to welcoming both athletes and spectators."