In February 2001, former schoolteachers Ann Bancroft and Liv Arnesen became the first women to cross the Antarctic continent on foot. Against all odds, they walked, skied, or ice-sailed for nearly three months in temperatures as cold as -35?F, towing their 250-pound supply sledges across 1700 miles of terrain riddled with rotten ice and deadly, hidden crevasses. Haunted by the failures of those who had attempted the crossing before them, they raced...