Kubkowski, who is from the northeastern Polish town of Giżycko, embarked on his record-breaking, 170-kilometre attempt on Monday morning, the rmf24.pl website reported.
Across the Baltic in under 60 hours
He expected to cover the distance between the Polish port of Kołobrzeg and Sweden’s Ystad in less than 60 hours.
On Tuesday morning, the swimmer was already halfway through to the Swedish coast, near Bornholm Island, reporters were told.
The second part of the swim promised to be more demanding, with Kubkowski likely to grow fatigued, but the weather was favourable, “sunny with practically no wind and minimal waves,” rmf24.pl reported.
The Polish swimmer was being accompanied by his team, which provided him with directions and special regenerative meals from a nearby boat, organisers said.
Raising money for ill children
As well as attempting to make swimming history, Kubkowski was also raising funds for children with cancer, rmf24.pl reported.
As he entered the waters on Monday morning, Kubkowski said he felt “a motley of emotions,” adding that it had taken “a year of hard work” to prepare for the record-breaking swim across the Baltic Sea.
“I’ll try to do everything in my power to achieve this aim,” Kubkowski said.
His progress could be followed on his Instagram.
Source: rmf24.pl, kolobrzeg.naszemiasto.pl