Seven channels, eight years
Guinness World Records lists the full sequence with dates. Cook Strait on 24 February 2017. The Tsugaru Strait in Japan on 5 July 2022. The English Channel on 9 August 2023, the North Channel between Ireland and Scotland on 24 August 2023, and the Strait of Gibraltar on 11 September 2023. The Catalina Channel in California on 16 July 2024, and finally the Ka'iwi, or Molokai, Channel on 23 and 24 October 2024.
Three of the seven fell inside six weeks in 2023 — the English Channel, the North Channel and Gibraltar — which is a punishing compression of the schedule. The North Channel in particular is regarded as among the hardest of the group for its cold water and jellyfish.
Thirteen hours to Oahu
The last crossing was the longest recorded here: 42 kilometres from Molokai to Oahu across the Ka'iwi Channel, swum overnight on 23 and 24 October 2024 in 13 hours and 18 minutes.
Guinness certifies her age at completion as 20 years and 227 days, calculated from a date of birth of 11 March 2004. That figure is what carries the record: the Oceans Seven has been completed by a growing number of marathon swimmers, but not by anyone younger.
Twelve years old in Cook Strait
The most striking date in the list is the first. Cook Strait, the stretch of water between New Zealand's North and South Islands, was crossed on 24 February 2017, when O'Reilly was still 12 — two weeks short of her thirteenth birthday.
A gap of more than five years then follows before the Tsugaru Strait in July 2022, and the remaining five swims are packed into the 27 months after that. The shape of the record is therefore a childhood crossing at home, a long pause, and then a concentrated campaign through the world's hardest channels.
What the Oceans Seven is
The Oceans Seven is open-water swimming's answer to the Seven Summits: a set list of seven channel crossings, all of them long, cold or tidally difficult, and all swum under rules that generally prohibit wetsuits and any assistance from the support boat.
Each swim requires an observer, a pilot boat and, in most of these channels, a licensed association to ratify it. That is why completions are countable and why a youngest-ever record can be certified at all: the paperwork behind each crossing is as much a part of the achievement as the swimming.
What is documented — and what is not
The Guinness entry is exact on dates, times, distances, ages and nationality. It carries no quotes from O'Reilly, no account of her training, no coach or club, and no description of the conditions she met in any of the seven channels.
It also stops at the record. Nothing in the source used here says what she has swum since October 2024, whether she competes in pool or open-water racing, or what she does outside the sport. Those are gaps in the published record, and this entry does not fill them.
| Person | Country | Milestone | Age / Stat |
|---|
What is documented — and what is not
✓ Documented
- Date of birth 11 March 2004; youngest person to swim the Oceans Seven at 20 years 227 days (Guinness World Records)
- Final swim: Ka'iwi/Molokai Channel, 42 km, 13 hr 18 min, 23-24 October 2024
- Full dated list of all seven channels, beginning with Cook Strait on 24 February 2017
? Unverified, disputed or wrong
- No quotes, coach, club or training detail in the record entry
- No description of conditions on any individual swim
- No reporting located on her activity after October 2024
Questions people ask about Caitlin O'Reilly
How old is Caitlin O'Reilly?
Guinness gives her date of birth as 11 March 2004. She was 20 years and 227 days old when she completed the Oceans Seven in October 2024.
What are the Oceans Seven?
Seven set channel crossings: Cook Strait, the Tsugaru Strait, the English Channel, the North Channel, the Strait of Gibraltar, the Catalina Channel and the Ka'iwi (Molokai) Channel.
Which swim finished the set?
The Ka'iwi Channel from Molokai to Oahu, 42 kilometres, in 13 hours and 18 minutes on 23-24 October 2024.
How young was she for her first crossing?
Twelve. She swam Cook Strait on 24 February 2017, two weeks before her thirteenth birthday.
Is Caitlin O'Reilly on Wikipedia?
No dedicated Wikipedia biography was confirmed for this entry. Her name appears in coverage of the Oceans Seven.
Who coached her?
The Guinness record entry names no coach, club or training programme.
Where is Caitlin O'Reilly now?
No source used here reports on her swimming after October 2024.
Did she swim in a wetsuit?
Oceans Seven crossings are generally swum under rules that prohibit wetsuits. The record entry used here does not discuss her equipment.
Quick quiz: how well do you know Caitlin’s story?
Which swim completed Caitlin O'Reilly's Oceans Seven?
How old was she when she swam Cook Strait?
How long did the final crossing take?
Sources
- Youngest person to swim the Oceans Seven (female) — Guinness World Records
Checked by the Geniuses.club editorial team. Ages are given as of September 2026.
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