Sarah Thomas is an ultra-marathon swimmer who holds the world record for the longest continuous (unassisted, non-wetsuit) swim in current-neutral conditions — 104.6 miles over 67 hours in Lake Champlain (2017).

Just months later, she was diagnosed with aggressive breast cancer at age 35. One year after completing treatment, she made history again, becoming the first person to complete a four-way crossing of the English Channel (54 hours, 10 minutes).

Sarah has continued to redefine what’s possible, including the first two-way crossing of the North Channel (21 hours, 46 minutes in freezing, jellyfish-filled waters). Her swim résumé spans the globe, with multiple “firsts” across legendary channels and lakes.

At Beyond The Breakers 2025, Sarah will share some of her keys to success in open water and marathon swimming — from mental resilience to physical preparation — offering invaluable insight for swimmers of all levels.

For more information on Sarah, check out her website, Facebook and Instagram!