OmniathlonOWS

The longest open water swims in the world

Open water races from 10 kilometres up, ordered by distance: marathon swims, crossings and ultra-distance events. For each race: next edition, location and distances on offer.

Sea, lake or river
Sea 53Lake 22River 22
1
91.8 km
40 Bridges - Double Manhattan Island Swim
New York City, United States
2
84 km
Vidösternsimmet — Värnamo
Värnamo, Sweden
3
64 km
Bodensee Dreiländerquerung 3LQ
Lindau, Germany
  1. 4
    57 km
    Maratón Acuática Internacional Santa Fe – Coronda
    Santa Fe, Argentina
    last editionFeb 1, 202657kmRiver
  2. 5
    50 km
    Travesía Internacional Amazónica
    Iquitos, Peru
    last editionAug 23, 202625km · 50kmRiver
  3. 6
    48 km
    Maratón Santa Fe – Coronda para Aficionados
    Santa Fe, Argentina
    Nov 28, 202648kmRiver
  4. 7
    45.9 km
    20 Bridges Swim Around Manhattan
    New York City, United States
    45.9kmSea
  5. 8
    36 km
    Manly to Bundeena 36km
    Manly, Australia
    last editionDec 14, 202536kmSea
  6. 9
    36 km
    Swim Loch Ness 2026 — Fort Augustus → Lochend
    Fort Augustus, United Kingdom
    last editionJul 1, 202636kmLake
  7. 10
    36 km
    Capri-Napoli Marathon
    Napoli, Italy
    last editionSep 5, 202636kmSea
  8. 11
    35 km
    Swim Loch Lomond End-to-End 2026
    Balloch, United Kingdom
    last editionJun 8, 202635kmLake
  9. 12
    35 km
    BLDSA Loch Lomond
    Arrochar, United Kingdom
    last editionAug 28, 202635kmLake
  10. 13
    34 km
    Wörthersee Swim Austria
    Klagenfurt, Austria
    last editionSep 4, 202610km · 17km · 34kmLake
  11. 14
    34 km
    Alpen Adria Wörthersee Crossing
    Pörtschach am Wörthersee, Austria
    last editionSep 12, 202610km · 17.5km · 34kmLake
  12. 15
    34 km
    La II Ultra Travesía
    Cancas / Los Órganos, Peru
    34kmSea
  13. 16
    33.8 km
    BLDSA 2 Way Windermere
    Glenridding, United Kingdom
    last editionAug 1, 202633.796kmLake
  14. 17
    33 km
    Le Flow des Gabarriers
    Cognac, France
    last editionJun 13, 20263km · 16km · 33kmRiver
  15. 18
    32 km
    62e Traversée Internationale du Lac St-Jean 32km
    Roberval, Canada
    last editionJul 25, 202632kmLake
  16. 19
    32 km
    À l'eau Péribonka
    Péribonka, Canada
    last editionJul 25, 202632kmRiver
  17. 20
    31 km
    16th UltraEbre Swim Marathon
    Tortosa, Spain
    Jul 3, 202731kmRiver
  18. 21
    30 km
    OncoSwim
    L'Estartit, Spain
    last editionMay 30, 20261.5km · 30kmSea
  19. 22
    30 km
    ULTRASWIM IBIZA 2026 — Ultra & Mini
    Ibiza, Spain
    last editionMay 30 – 31, 2026 · 2 race days1km · 5km · 30kmSea
  20. 23
    30 km
    X-WATERS Volga
    Nizhny Novgorod, Russia
    last editionJul 26, 20265km · 10km · 30kmRiver
  21. 24
    30 km
    Three Rivers Marathon Swim
    Pittsburgh, United States
    last editionAug 29, 202630kmRiver
  22. 25
    30 km
    Periplo Isola d'Ischia
    Casamicciola Terme, Italy
    Sep 26, 202630kmSea
  23. 26
    30 km
    Desafio Costa Esmeralda 30K
    Bombinhas, Brazil
    30kmSea
  24. 27
    29 km
    NEKOWSA Lac Massawippi Marathon Swim (18 mi)
    Ayer's Cliff, Canada
    last editionAug 3, 202614.484km · 28.968kmLake
  25. 28
    27.5 km
    Rose Pitonof Swim
    New York, United States
    last editionAug 8, 202627.5kmSea
  26. 29
    27 km
    Batalla de Rande
    Vigo, Spain
    last editionJun 20, 202627kmSea
  27. 30
    26 km
    Another Level Performance Palm to Shelly 26km swim
    Sydney, Australia
    last editionApr 11, 202610km · 26kmSea
  28. 31
    26 km
    56th International swimming cross of Toroneos Gulf
    Nikiti, Greece
    last editionJul 25, 202626kmSea
  29. 32
    25.9 km
    Ederle-Burke Swim
    New York, United States
    last editionSep 12, 202625.9kmSea
  30. 33
    25 km
    MC Swim Challenge
    Marseille, France
    last editionJun 20, 202625kmSea
  31. 34
    25 km
    Défi de la Salamandre 2026 (Coupe France Eau Libre) — Villiers-sur-Loir
    Villiers-sur-Loir, France
    last editionJul 4, 20265km · 10km · 25kmRiver
  32. 35
    25 km
    Great Masurian Lakes Crown
    Giżycko, Poland
    last editionAug 1, 202619km · 23km · 25kmLake
  33. 36
    25 km
    Traversée du Lac Saint-Joseph
    Fossambault-sur-le-Lac, Canada
    last editionAug 9, 20266km · 10km · 25kmLake
  34. 37
    25 km
    KotlinRace
    Saint Petersburg, Russia
    last editionAug 9, 202625kmSea
  35. 38
    25 km
    Ohrid Swimming Marathon
    Ohrid, North Macedonia
    last editionAug 22, 202625kmLake
  36. 39
    25 km
    Aquaman Saint-Tropez
    Saint-Tropez, France
    Oct 23, 20265km · 10km · 25kmSea
  37. 40
    25 km
    Port to Pub
    Fremantle, Australia
    Mar 20, 202719.7km · 25kmSea
  38. 41
    25 km
    Ocean Swim Series - Lake Karapiro
    Cambridge, New Zealand
    Apr 3, 202710km · 25km · 25kmLake
  39. 42
    24 km
    Downhill Swim
    Kuusamo, Finland
    last editionAug 1, 202612km · 24kmRiver
  40. 43
    24 km
    Travessia 14 Bis
    Bertioga, Brazil
    Nov 7, 202624kmSea
  41. 44
    24 km
    U24 Safety to Sorrento
    Sorrento, Australia
    Feb 13, 20276km · 12km · 24kmSea
  42. 45
    22 km
    Bodensee Openwater — Friedrichshafen-Romanshorn
    Friedrichshafen, Germany
    last editionAug 1, 202611km · 22kmLake
  43. 46
    22 km
    Da Porto a Porto
    Monte Argentario, Italy
    last editionAug 10, 202622kmSea
  44. 47
    22 km
    IJsselmeer Zwemmarathon
    Enkhuizen, Netherlands
    last editionAug 15, 202622kmLake
  45. 48
    22 km
    Swim4Brains
    Medemblik, Netherlands
    last editionAug 22, 202622kmLake
  46. 49
    22 km
    Travesía El Reto Olaya Inverso
    La Punta, Peru
    Nov 7, 202622kmSea
  47. 50
    22 km
    Reto Acapulco La Prueba Reina
    Acapulco, Mexico
    Nov 7, 20266.4km · 11km · 22kmSea
  48. 51
    21 km
    Mega do Ita 2026
    Bertioga, Brazil
    last editionMay 23, 202621kmSea
  49. 52
    21 km
    UltraOceanMan Balkhash
    Shashubay, Kazakhstan
    last editionAug 28 – 29, 2026 · 2 race days21kmLake
  50. 53
    21 km
    Maratón Acuática Villa Urquiza-Paraná
    Paraná, Argentina
    Dec 12, 202621kmRiver
  51. 54
    21 km
    UltraOceanMan Tabarca
    Tabarca, Spain
    May 28 – 29, 2027 · 2 race days21kmSea
  52. 55
    20 km
    Geo Bay Cool Water Classic
    Dunsborough, Australia
    last editionNov 15, 202520kmSea
  53. 56
    20 km
    Aguas Abiertas Concordia–Puerto Yerúa 2026
    Concordia, Argentina
    last editionJan 24, 202611km · 20km
  54. 57
    20 km
    Lake Argyle Swim
    Kununurra, Australia
    last editionMay 2, 202610km · 20kmLake
  55. 58
    20 km
    Egadi Ultra Swim | La Gran Fondo 2026
    Favignana, Italy
    last editionMay 30, 202620kmSea
  56. 59
    20 km
    Desafío Islas Cíes X2 2026 — 20km
    Vigo, Spain
    last editionJun 27, 202610km · 12km · 20kmSea
  57. 60
    20 km
    Swim GP - Travessia Oeiras-Cascais
    Cascais, Portugal
    last editionJul 18, 20265km · 10km · 20kmSea
  58. 61
    20 km
    Swim Around Keppel 2026 (SAK2026)
    Great Keppel Island, Australia
    last editionJul 24, 20261km · 6km · 20kmSea
  59. 62
    20 km
    MČR Dálkové Plavání — Račice 5km+20km
    Račice, Czechia
    last editionAug 29, 20265km · 20kmRiver
  60. 63
    20 km
    Travesía Uniendo Faros
    Alicante, Spain
    Sep 19, 20265km · 10km · 20kmSea
  61. 64
    20 km
    Swimjunkie Challenge: Caramoan — 10th Year
    Caramoan, Philippines
    Oct 4, 202610km · 15km · 20kmSea
  62. 65
    20 km
    Súper Fondo 20k Telchac
    Telchac Puerto, Mexico
    Nov 8, 202620kmSea
  63. 66
    20 km
    Maratón Acuática San Pedro — 20K
    San Pedro, Argentina
    Nov 8, 202620kmRiver
  64. 67
    20 km
    Serre-Ponçon Swim Challenge
    Savines-le-Lac, France
    Jul 3, 202712km · 20kmLake
  65. 68
    20 km
    Swim GP - Travessia Lisboa-Cascais
    Lisboa, Portugal
    20kmSea
  66. 69
    19.7 km
    Rottnest Channel Swim
    Perth, Australia
    Feb 20, 202719.7kmSea
  67. 70
    19.3 km
    Swim Around Charleston
    Charleston, United States
    Oct 3, 202619.312kmRiver
  68. 71
    18.5 km
    Quibr'Enez Parcours 4/5 — Locmariaquer→Houat
    Locmariaquer, France
    last editionAug 15, 202618.5kmSea
  69. 72
    18 km
    POWSA Gdańsk Bay Swim
    Gdańsk, Poland
    last editionJul 25, 202618kmSea
  70. 73
    18 km
    13ª Mar de las Calmas — La Restinga
    La Restinga, Spain
    Sep 26, 20262.5km · 6.5km · 18kmSea
  71. 74
    18 km
    Vuelta de Obligado — San Pedro
    San Pedro, Argentina
    Nov 14, 202618kmRiver
  72. 75
    18 km
    Grand Prix Vuelta de obligado
    San Pedro, Buenos Aires, Argentina
    Nov 14, 202618kmRiver
  73. 76
    17.7 km
    Chillswim Windermere 11 Miles End to End
    Windermere, United Kingdom
    last editionSep 5, 202617.703kmLake
  74. 77
    16.9 km
    BLDSA Windermere
    Newby Bridge, United Kingdom
    last editionAug 29, 202616.898kmLake
  75. 78
    16.1 km
    Swim the Suck
    Chattanooga, United States
    Oct 3, 202616.093kmRiver
  76. 79
    16 km
    Circuito Maratour 2026 — Mahi-Mahi (Salvador)
    Salvador, Brazil
    last editionMar 28, 20261.5km · 3km · 16km
  77. 80
    16 km
    Maratour Village Itaparica
    Itaparica, Brazil
    Sep 19, 20261.5km · 3km · 16kmSea
  78. 81
    16 km
    UltraMaratour — Itaparica–Mutá
    Itaparica, Brazil
    Sep 20, 20261.5km · 3km · 16kmSea
  79. 82
    16 km
    Perhentian Island Challenge
    Perhentian, Malaysia
    Oct 10, 202616kmSea
  80. 83
    16 km
    Circuito Maratour — Itaparica (novembro)
    Itaparica, Brazil
    Nov 1, 20261.5km · 3km · 16kmSea
  81. 84
    15 km
    Ultra do Ita 2026
    Bertioga, Brazil
    last editionMar 14, 202615kmSea
  82. 85
    15 km
    Travesía South West Tenerife 2026
    Adeje, Spain
    last editionMay 2, 202615km
  83. 86
    15 km
    Gran Fondo Golfo di Castellabate 2026
    Castellabate, Italy
    last editionJun 28, 202615kmSea
  84. 87
    15 km
    Swim4Dreams Open Water Festival 2026 — Călărași
    Călărași, Romania
    last editionJul 23, 2026500m · 1.5km · 15kmRiver
  85. 88
    15 km
    La Gola - Farella
    Llançà, Spain
    last editionAug 2, 202610km · 15kmSea
  86. 89
    15 km
    Canaqua Welland II
    Welland, Canada
    last editionAug 30, 20265km · 10km · 15kmRiver
  87. 90
    15 km
    Triple Corona Illas Atlánticas
    Baiona, Spain
    last editionSep 12, 202615kmSea
  88. 91
    15 km
    Scilly Swim Challenge 1-Day
    St Mary's, United Kingdom
    Sep 20, 202615kmSea
  89. 92
    15 km
    20th Anniversary of the Clean Half - Extreme Marathon Swim
    Stanley, Hong Kong
    Oct 3, 202615kmSea
  90. 93
    15 km
    Aquaman Somabay
    Somabay, Egypt
    Oct 30, 20265km · 10km · 15kmSea
  91. 94
    15 km
    Travessia Morro a Morro — 15K
    Vila Velha, Brazil
    Oct 31 – Nov 1, 2026 · 2 race days15kmSea
  92. 95
    15 km
    The Cold Half
    Stanley, Hong Kong
    Jan 31, 2027400m · 1.5km · 15kmSea
  93. 96
    15 km
    Cliff to Bridge
    New Norfolk, Australia
    Feb 6, 202715kmRiver
  94. 97
    14.5 km
    Authentic Marathon Swim — Marathon
    Artemision, Greece
    5km · 10km · 14.5kmSea
  95. 98
    14 km
    Quibr'Enez Parcours 3/5 — Belle-Île→Quiberon
    Quiberon, France
    last editionAug 1, 202614kmSea
  96. 99
    14 km
    Wakenitzmann Lübeck
    Lübeck, Germany
    last editionAug 30, 202614kmRiver
  97. 100
    14 km
    Nadando Los Cabos
    San José del Cabo, Mexico
    Nov 14, 20262km · 7km · 14kmSea

Staged swims

These are swum in stages, spread over several days: their totals don't compare with a single continuous swim, so they get a list of their own.

  1. 1
    193 km
    8 Bridges Hudson River Swim
    🚩Staged swim
    New York, United States
    193kmRiver
  2. 2
    181 km
    X-WATERS Самара 181
    🚩Staged swim
    Samara, Russia
    last editionAug 19 – 25, 2026 · 7 race days30km · 181kmRiver
  3. 3
    150 km
    Extreme 150 km Volga Odyssey
    🚩Staged swim
    Saratov, Russia
    last editionAug 4 – 8, 2026 · 5 race days150kmRiver
  4. 4
    50 km
    Aldeia do Mato Open Water Swimming 2026
    🚩Staged swim
    Abrantes, Portugal
    last editionJun 5 – 7, 2026 · 3 race days10km · 11km · 50kmLake
  5. 5
    33.3 km
    UltraSwim 33.3 #12 Croatia 2026 — Hvar
    🚩Staged swim
    Stari Grad, Croatia
    last editionMay 15 – 18, 2026 · 4 race days16.65km · 22.2km · 33.3kmSea
  6. 6
    33.3 km
    UltraSwim 33.3 Switzerland 2026 — Lac Léman
    🚩Staged swim
    Genève, Switzerland
    last editionJul 24 – 27, 2026 · 4 race days13km · 16.65km · 33.3kmLake
  7. 7
    33.3 km
    #16MONTENEGRO 2026
    🚩Staged swim
    Montenegro
    Oct 2 – 5, 2026 · 4 race days16.65km · 33.3kmSea
  8. 8
    33.3 km
    UltraSwim 33.3 Greece
    🚩Staged swim
    Milos, Greece
    Jun 3 – 6, 2027 · 4 race days33.3kmSea
  9. 9
    33 km
    Morocco Swim Trek — Dakhla
    🚩Staged swim
    Dakhla, Morocco
    Nov 24 – 29, 2026 · 6 race days3km · 5km · 33kmSea
  10. 10
    16.7 km
    #17BARCELONA [Costa Brava]
    🚩Staged swim
    Barcelona, Spain
    Oct 17 – 18, 2026 · 2 race days16.65kmSea

The relays

Here the distance belongs to a team: these are relays, and the total is not one swimmer's distance.

  1. 1
    300 km
    300km Revezamento em Águas Abertas
    Porto Belo, Brazil
    Mar 16, 2027300kmSea
  2. 2
    100 km
    100km Revezamento em Águas Abertas
    Porto Belo, Brazil
    Oct 10, 2026100kmSea
  3. 3
    45.9 km
    20 Bridges Swim Around Manhattan — Relay
    New York, United States
    45.9kmSea
  4. 4
    35 km
    Los Cabos Ocean Relays
    Los Cabos, Mexico
    Jan 23, 202735kmSea
  5. 5
    29 km
    Nantucket to Martha's Vineyard Jaws 18-Mile Open Ocean Relay Swim
    Edgartown, United States
    last editionJul 22, 202628.968kmSea
  6. 6
    23 km
    5ª Swim for ELA
    Calafat, Spain
    last editionMay 23, 202623kmSea
  7. 7
    13 km
    Havkraft — Årøsund til Assens
    Årøsund, Denmark
    last editionAug 16, 202613kmSea