The original post: /r/todayilearned by /u/RealisticBarnacle115 on 2024-11-14 15:20:58.

Original Title: TIL backyard ultra, a type of ultramarathon where competitors must run 6.706 km within one hour, repeatedly. The last runner to complete a lap is declared the winner and the only finisher, with all others receiving a “DNF”. The longest distance record is 110 laps, covering 737 km over five day.