Your
route

800m Distance

A very achievable swim and the ideal choice for first-timers. You’ll follow the current downstream to the finish line on the riverbank at Lanesborough. Equivalent to 32 lengths of a 25m pool.

Cut-off time: 40 minutes

3.5km Distance

Starting further upstream, this route offers more time to enjoy the sweep and bends of the Shannon as it guides you downstream to Lanesborough. A rewarding challenge for swimmers with some open water experience.

Cut-off time: 1 hour 30 minutes

5.8km Distance

Set yourself a true test on this longer course. The river twists and turns as you make your way downstream, demanding stamina and focus. Suited to confident, experienced swimmers. Wetsuits are compulsory if the water temperature is 11°C or below.

Cut-off time: halfway in 1 hour 30 minutes

12km Distance

The ultimate adventure and Ireland’s longest downstream swim. Over 12km, you’ll follow the Shannon’s broad curves and winding channels, carried by the flow but challenged by distance and endurance. Strictly for experienced athletes: swimmers must be 18+, with proof of completing a 3.9km race within the past 12 months. Wetsuits are compulsory, and a GPS tracker will be provided for safety.

Cut-off times: halfway (5.8km) in 2 hours 15 minutes; final cut-off 5 hours

Safety & Entry Requirements

The water temperature at this time of year is usually around 12°C. To take part, you’ll need some open water swimming experience and should choose your distance carefully - only enter a distance you’ve comfortably swum before in similar conditions.

Tow-floats must be worn by all swimmers. These can be rented during entry or on the day at the information desk. Our team of kayakers and safety boats will be with you throughout the swim, and a medical team will also be on hand for your safety and peace of mind.

Part of the Great Swim Trilogy

This is the first event of the Gaelforce Great Swim Trilogy. Swim in the River Shannon, Lough Derg and Killary Fjord to complete the trilogy and collect your exclusive Gaelforce Great Swim Trilogy branded mystery gift! Sign up for all three at the same time before the deadline on the 16 May 2026 to qualify.

We’ve designed the Great Swim Trilogy to follow the journey from lake to river to sea. With events in late spring, mid-summer and autumn, you can build your experience and distances as you go. The perfect challenge for your swimming year.
Gaelforce Great Lake Swim | Gaelforce Great Fjord Swim

Route map