An Irishman was the first person in history to complete the Oceans Seven. Another Irishman will mostly likely become the first person in history to complete The Toughest Thirteen if all goes to plan.

Background

The Toughest Thirteen (T13 or MSF Toughest Thirteen) is a series of 13 difficult open water swims created by Evan Morrison in 2019 as an challenging marathon swimming alternative to the Oceans Seven.

The swims include the following. For more details, visit here.

• ʻAlenuihāhā Channel: 47 km (minimum) swim between the islands of Hawaii and Maui in the state of Hawaii
• Beltquerung: 25 km swim across the Fehmarn Belt in the Baltic Sea between Denmark and Germany
• Dál Riata Channel: 21 km swim between Mull of Kintyre in Scotland and Ballycastle in Northern Ireland
• Big Swim Derwent River Marathon: 34 km swim in the Derwent River in Tasmania, Australia
• False Bay: 33 km swim between Rooi Els to Miller’s Point in South Africa
• Fastnet Rock: 15.6 km (minimum) swim from County Cork on the Irish mainland
• Foveaux Strait: 29 km (minimum) between Stewart Island/Rakiura and from New Zealand’s South Island
• Gulf of the Farallones: 33 – 48 km swim between the Farallon Islands and the California mainland or the Golden Gate Bridge
• Loch Ness: 36 km swim across the famed lake in Scotland
• Monterey Bay: 37 km swim across the bay along the central coast of California, USA
• Round-Trip Angel Island: 16 km swim between Aquatic Park and Angel Island in San Francisco Bay in California, USA
• Strait of Juan de Fuca: 17 km swim between Vancouver Island in British Columbia, Canada and the state of Washington, USA
• Lago Titicaca: world’s highest commercially navigable lake located on the border of Peru and Bolivia

Oceans Seven

Stephen Redmond of Ireland was the first person to complete the Oceans Seven in 2012. Another Irishman John Charles Curley (42, Ireland, MSF bio here, @johncharles.curley) may be the first person to complete the T13, perhaps within 1-2 years.

Curley T13 Update

After his New Year’s Day swim in Bolivia, Curley has now completed 10 of the T13 swims.

1. October 2022: Monterey Bay crossing in northern California in 14 hours 52 minutes
2. June 2023: Beltquerung across the Fehmarnbelt in the Baltic Sea between Denmark and Germany in 7 hours 35 minutes
3. January 2024: Derwent River Big Swim in Tasmania, Australia in 8 hours 52 minutes
4. July 2024: Dál Riata Channel crossing between Mull of Kintyre and Torr Head in Northern Ireland in 10 hours 45 minutes
5. June 2024: Fastnet Rock Swim from the Fastnet Lighthouse to Baltimore in 6 hours 55 minutes
6. January 2025: False Bay in South Africa in 10 hours 38 minutes with Linda Clarke and  escort pilot Roger Finch
7. January 2025: Foveaux Strait between Stewart Island to South Island in New Zealand with escort pilot Philip Rush
8. September 2025: Round-Trip Angel Island between Aquatic Park and Angel Island in San Francisco Bay in 6 hours 36 minutes with escort pilot Clare O’Connor
9. September 2025: Strait of Juan de Fuca between the USA and Canada in 8 hours 13 minutes with escort pilot Ger Kennedy and Brandyn Sampson and observer Andrew Malinak
10. January 2026: 16.32 km Lago Titicaca with Ger Kennedy in 5 hours 47 minutes

Although Curley was planning to attempt a marathon swim in Lake Titicaca between Peru and Bolivia, he ended up executing Plan B by swimming in the lake from Isal K’oa and finishing on the Inca Steps in Yumani on the Isla del Sol on the Bolivia side of the lake. His start coordinates were -15.967645 -69.230314 and his finish coordinates 16.038764 -69.143975.

Kennedy reports, “It was an incredibly tough swim at high altitude of 3,850m for John Charles with a distance of over 16 km. He had 10 days of pre-altitude acclimatization while battling stomach parasites with antibiotics. He really struggled to get to start line, but with 5 hours of swim training at Copacabana over a few days, he dug deep to overcome

On his swim day, we got perfect wind direction conditions with average water temp of 15.4°C with pre-swim offerings to the Andean gods for safe passage. He got the swim completed with special thanks to Andeas Way travel agent and La Autoridad Binacional Autónoma del Sistema Hídrico del Lago Titicaca, and the Armada Bolivia for their support.“

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