Jono Ridler: Ultra-marathon swimmer on completing record-breaking swim across the Hauraki Gulf - Heather du Plessis-Allan Drive

Endurance athlete Jono Ridler has spent a night in hospital, recovering from a 33 hour, record-breaking swim.

The 33-year-old swam almost 100 kilometres from Great Barrier Island to Campbells Bay, raising awareness of damage to the Hauraki Gulf.

He also beat New Zealand's open water swimming record by about 20 kilometres.

Ridler says he's surprised how his body feels after his ordeal.

"My eyes are swollen from the goggles, my mouth and tongue are pretty torn to shreds from all the saltwater washing around. But otherwise, yeah, I'm feeling good."

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