The swimmers attempting to navigate the dangerous 30-mile stretch had to abandon the effort Thursday night.
Six members of the Night Train Swimmers started their relay around 6:30 a.m. Thursday, but around 8 p.m. the current became too strong and the group was forced to give-up just six miles from the Golden Gate Bridge.
"We were facing an ebb that was equal to stronger than our swimming speed, so we were going backwards," said Phil Cutti from Night Train Swimmers.
"So we basically swam in place for four hours and we realized that this isn't going to work," said Vito Bialla from Night Train Swimmers.
The group is raising money for the Wounded Warrior Project which it supports service members and their families. They plan to attempt this swim again in the coming months.
The Night Swimmers are made up of six local swimmers: Vito Bialla, Darrin Connolly, Phil Cutti, David Holscher, Joe Locke and John Mathews.
It's a six-person relay and each member swam for about an hour in three rotations. The water is cold, choppy and current-ridden, making this one of the toughest open water swims around. A 2010 attempt at the swim was aborted when one of the swimmers came down with extreme hypothermia after just 42 minutes in the water. The swim will go through what's been called "The Red Triangle" due to its historically high concentration of Great White Shark attacks.
Check out their site for updates and information on how to donate to their cause.
Terry McSweeney contributed to this report.