93-year-old Keiko Fukuda is the highest-ranking woman in judo history. She's also the last surviving personal student of Jigoro Kano (the founder of judo).
She began her training under Kano at the Kodokan in Tokyo in 1935, at the behest of her grandfather, Hachinosuke Fukuda, who'd once taught Kano in Tenshin Shinyo. Kano made an exception for her, out of respect for his old sensei, and began allowing women to train at the Kodokan.
In 2001, she became the first woman to recieve a red belt (signifying 9th dan) from the US Judo Federation, which has awarded only three red belts in its history. She is also the only surviving red belt within the USJF.
Today, Keiko Fukuda still teaches twice a week in her dojo in the San Fransisco Bay area.