A Scot has set a new world record for the fastest swim across the Cook Strait - the waters between New Zealand's North and South Islands. Andy Donaldson, 31, swam through the night to complete the 23km route in four hours and 33 minutes. It was the third leg of seven comprising the Oceans Seven challenge.

Yes, you can swim between the North and South Islands of New Zealand across the Cook Strait, but it is one of the world's most dangerous and unpredictable marathon swims. The distance is approximately 22 kilometers (14 miles) at its narrowest point, but swimmers often cover much more due to powerful and complex tidal currents. The strait connects the Tasman Sea with the South Pacific Ocean, and the tides are often out of phase, creating violent eddies and "washing machine" conditions. The water temperature is typically around 14°C to 18°C (57°F to 64°F), requiring significant cold-water acclimation. As of 2026, fewer than 150 people have successfully completed the crossing, and it remains a member of the "Ocean's Seven" challenge. Beyond the physical endurance, swimmers must contend with unpredictable winds and the occasional shark sighting. All attempts are strictly monitored by official guides and support boats to manage the heavy commercial ferry traffic and ensure the swimmer's safety in one of the world's toughest aquatic environments.