- Yiannis Kouros
- 10:10:30:36 day(s):hour(s):minute(s):second(s)
- United States (New York City)
Yiannis Kouros (Greece) ran 1,000 miles (1,609 kilometres) in 10 days 10 hours 30 minutes 36 seconds during the 1988 International Association of Ultrarunners (IAU) World Championship in New York City, USA, on 20–30 May 1988.
As of January 2015, the IAU no longer classifies World Best Performances by surface, creating a single combined list of fastest times.