The race is organised by the Neretva Boatmen's Association.
Prime Minister Andrej Plenković attended the event, meeting local government leaders from the Neretva River Valley, the leadership of the Neretva Boatmen's Association and the rowers before the race.
He described the race as a cherished tradition of the Neretva Valley and said he had discussed agglomeration projects with the mayors and municipal heads of the surrounding towns and municipalities, covering Metković, Ploče and Opuzen, as well as the construction of a dam on the Neretva to prevent seawater from entering the river's upper reaches.
"This is extremely important for the fauna in the Neretva River, but also for agriculture. The government is investing in a motorway from Vid, which is part of Metković, to Nova Sela. It is a huge project that will significantly improve the quality of life for people in Metković. We have excellent cooperation with the mayor and county prefect. I believe the Bpat Marathon will continue to promote this beautiful tradition," the prime minister said.
The route from Metković to Ploče is 22.58 kilometres long. Alongside the Croatian competitors, a team from Sombor in Serbia is also taking part.
Organisers said competitors make around 9,000 strokes from the bridge in Metković to the finish in Ploče in boats that have long been part of life in the Neretva Valley.
The marathon is an amateur sporting competition held in traditional wooden Neretva boats built according to strict rules. Each competing boat has a crew of 10 rowers, a drummer and a coxswain.
In addition to its sporting character, the race, held since 1998, has become one of the most important tourist events in southern Croatia, attracting visitors from around the world.
Numerous events are held ahead of the race, including the women's boat marathon.
Plenković was accompanied in Metković by ministers Branko Bačić, responsible for spatial planning, construction and state assets; Finance Minister Tomislav Ćorić; Agriculture Minister David Vlajčić; and Environment and Green Transition Minister Marija Vučković.