Most runners in an ultra marathon

According to Official Guinness Records,

The most runners in an ultra marathon is 14,343 and was achieved by participants of the Comrades Marathon, which is an event organised by the Comrades Marathon Association (South Africa), and was run on a route from Pietermaritzburg to Durban, South Africa, on 30 May 2010.
The distance of the marathon was 89.28 km. The number of entries accepted for the event was 23,568. Entrants had to show they qualified for the Comrades by running a race of not less than 42.2km in less than 5 hours.
As it transpired, 16,480 runners started the race and 14, 343 completed it. They used Championship Timing System to track the times.

For a complete list of 2010 records, please visit 2010 Guinness Records in South Africa.

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