Olympic gold medallist Ferry Weertman and world champion Ana Marcela Cunha of Brazil are among the athletes set to compete at the International Swimming Federation Marathon Swim World Series leg in the Seychelles tomorrow.
Weertman, who won the 10 kilometres open water title at the 2016 Olympic Games in Rio de Janeiro, and Cunha are the leading competitors due to be in action.
Cunha arrives in the Seychelles having triumphed at the opening event of the campaign in Doha in February.
The Brazilian three-time world champion is bidding to retain the World Series crown she clinched last season.
A total of 81 athletes from 19 countries are due to compete across the men's and women's races.
Seychelles Swimming Association chairman David Vilot said the event gave the country the opportunity to "showcase our wonderful island, promote tourism and encourage swimmers to travel to our world class open water swimming destination".
"The Marathon Swimming World Series is the biggest competition we have ever hosted in the Seychelles and we feel very proud," added Seychelles Sports Council chief executive Giovanna Rousseau.
Both the men's and women's races, comprising six laps of a 1.6 kilometres course, are due to take place tomorrow.