Derwent River Series – Tasmanian Marathon Swimming Challenges
The Derwent River Series showcases a collection of marathon and ultra-distance swims set on the iconic Derwent River in Tasmania, Australia, one of the nation’s most historic and challenging open-water routes. Anchored by the renowned Derwent River Big Swim, this series offers swimmers a suite of endurance events ranging from classic long-course river crossings to unique freshwater and estuarine challenges against stunning natural backdrops.
The Derwent River Series celebrates endurance, resilience and the spirit of marathon swimming. All swims take place in Tasmania’s diverse waterways, from cool freshwater rivers and lakes to tidal estuarine sections offering a mix of technical challenges, scenic beauty, and personal achievement opportunities.
Featured Swims
Derwent River Big Swim – 34 km
The flagship event of the series, this iconic ultra-marathon swim starts at the New Norfolk Bridge in the Derwent Valley and finishes beneath Hobart’s Tasman Bridge. As Tasmania’s original 34-kilometre river swim, it challenges participants with variable tidal flows, changing water conditions.
Additional Series Challenges
The Derwent River Series extends beyond the flagship 34 km swim, offering a range of distances and settings suitable for different levels of marathon swimmers:
Tasman Bridge to Iron Pot Lighthouse – 22.3 km – Marathon swim from Tasman Bridge to Iron Pot Lighthouse in Storm Bay.
Bridgewater Bridge to Bruny Island – 41 km – Long river–to-island course from Bridgewater Bridge to Bruny Island (Dennes Point).
Frederick Henry Bay Big Swim – 12.3 km – Ocean swim across Frederick Henry Bay in Southern Tasmania.
Lake Pedder Big Swim – 43.5 km – Freshwater ultra swim in Lake Pedder, South West Tasmania.
Gordon River West Coast – 24.7 km – Cold-water marathon swim on Tasmania’s West Coast.
Lake St Clair / Leeawulenna – 14 km – Natural freshwater marathon swim at Lake St Clair.
Yingina / Great Lake – 26.84 km – Freshwater ultra swim across Great Lake on the Central Plateau.
New Norfolk Bridge to Opossum Bay – 49 km – Extended river–to–coastal ultra swim.
Bowen Bridge to Iron Pot Lighthouse – 30 km – Marathon swim from Bowen Bridge to Iron Pot Lighthouse.
New Norfolk Bridge to Iron Pot Lighthouse – 60 km – Ultra marathon from New Norfolk to Iron Pot Lighthouse.
When & How to Participate
The Derwent River Series events run predominantly across the Tasmanian swimming season, with flagship swims typically offered between November and March timed to coincide with optimal weather and water conditions.
To enter or learn more about individual swims, logistics, safety requirements, and support craft/escort boat guidelines, visit the official Derwent River Big Swim website and contact the organisers directly.