Just so we all know, I've now done a search:
"The first woman to sail solo around the world was Krystyna Chojnowska- Liskiewicz, starting the journey in the Canary Islands on February 28, 1976 and completing it there 401 days later, on April 2, 1978. In 1979, 29-year-old Naomi James braved the seas for 272 days to become the first woman to circumnavigate the globe via Cape Horn, the classic “Clipper Route.” "