List of largest running events

This list of the largest running events in the world is based on the number of participants. If available, the number of "registered" participants or finishers may be specified. Not all participants will actually complete a race. Running USA's Road Running Information Center estimates that, on average, 80%-85% of registrants will complete a race. If a yearly event has consistently high participation, the year in which that event had the largest number of participants has been listed.

With 110,000 participants, the Bay to Breakers race held on May 18, 1986 in San Francisco, California was recognized by the Guinness Book of World Records as the world's largest footrace. On October 10, 2010, 116,086 out of 160,000 registered runners in Manila were reported to have finished a run entitled "10.10.10 A Run for the Pasig River". An official for the ABS-CBN Foundation said that documentation of the event was being forwarded to Guinness World Records. The Guinness World Records certified Run for the Pasig River as having the most participants in a racing event on December 26, 2010.

* bold indicated number of race registrants, italics indicates number of race finishers

The Run Kerala Run held on 20 January 2015 in the Southern state of Kerala in India reportedly had a participation of 10 Million but wasn't considered for the record as there were around 32 various starting points spread across the state. But the main run flagged off by cricket icon Sachin Tendulkar was at Trivandrum and had an official participation of 1.23 Million which would make it the world's largest marathon. Other points like Cochin, Calicut, Quilon, etc. doesn't really have an exact figure and the projections are all approximate. Trivandrum is scheduled to host another major run event called Trivandrun in March which as per plan will have a participation of over 2 million runners.

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