A group of sea swimmers are planning to jump off every bridge over the River Liffey in Dublin city centre to raise money for charity.

The group plans to leap off 17 bridges in total, five bridges at a time. They jump, swim to the next bridge, climb out, and then repeat the process.

O’Connell bridge was their starting point this afternoon, and they ended at the Millennium bridge. One of them dressed as Elvis, and none of the swimmers wore wetsuits. Friend of the team Aoife Drumm said the water wasn’t too cold.

They decided to raise money for the Irish Cancer Society because one of the swimmers’ mothers died of cancer last year.

Their fundraising is cloaked in mystery. Their sponsor is a friend of group leader Robbie Clarke who agreed to donate an undisclosed sum of money anonymously. The mystery benefactor decides on the time and place of each jump, taking the tides into account. Tides have to be high, and the currents not too strong, to ensure the swimmers’ safety.

Mr Clarke has done this before—he grew up swimming in the Liffey, and he organised a swim to raise money for charity last year.

Ms Drumm says this could be the first of many organised bridge jumps for charity. Onlookers certainly seemed interested and willing to donate money, she said.