Rotorua's Mariana Morrison is diving head first into the Pacific Open Water Challenge in Samoa and believes she will be the first Maori woman to complete it.
But being no stranger to pushing herself to the limit, the seasoned swimmer is treating the challenge as just another notch in her belt of accomplishments.
Ms Morrison flew to Samoa on Saturday to take part in the challenge today and tomorrow, which covers a total of 15km.
She told the Rotorua Daily Post she was feeling "quite relaxed really" ahead of the competition.
"I'm actually using this as a build-up to another Motiti to Maketu swim. Nothing compares to that challenge so while this swim will have its own set of obstacles, I'm not too nervous."