- Who
- Elizabeth Tunna
- What
- 24, 351 year(s):day(s)
- Where
- United Kingdom (Chester)
- When
The youngest female to run 100 marathons is Elizabeth Tunna (UK, b. 23 Oct. 1986), aged 24 years 351 days when she completed the Chester Marathon in Chester, Cheshire, UK, on 9 October 2011