Courtesy of WOWSA, Kaieiewaho Channel, Hawaii.

Seven years ago this month, Australian Penny Palfrey attempted a solo 72-mile (115.8 km) crossing of the Kaieiewaho Channel between the islands of Kauai and Oahu.

It was her second attempt, starting from Ka’ena Point on Oahu with plans to finish on Kauai’s Nawiliwili harbor.

On her first attempt, she was supported by Jeff Kozlovich, Forrest Nelson, Bill Goding, and Neil Vaughan.

Both times, her crew protected her with a Shark Shield, but sharks were not her biggest obstacle to success.

Instead, she was stopped by marine life much smaller that she could not see or avoid, both the first and second attempts.

As the sun was setting, box jellyfish rose to the surface from the Pacific Ocean depths and stung her mercilessly. The venomous stings immediately put a halt to her swim and later caused convulsions, pain and deep red welts all over her body.

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