There are many races that are not standard distances or time frames but correspond to more natural phenomena. Examples that spring to mind are the Badwater Ultramarathon, 135 miles through Death Valley in the summer and the Spartathlon These races are quite often spectacular or challenging over and above the absolute time or distance involved.
- Badwater Ultramarathon
- Comrades Marathon
- Grand Union Canal 145 mile Race
- London to Brighton (deceasd)
- Two Oceans Marathon