The 35th Istanbul Marathon, an IAAF Gold Label event, will be run on Sunday.
Around 20,000 athletes are expected to compete in one of the three races of the event, formerly known as the Eurasia Marathon, this year sponsored by Vodafone.
A public walk through Bosphorus will also be held, during which about 100,000 people are expected to attend.
The marathon, which offers a total prize of one million USD, boasts the only course in the world involving two continents, Asia and Europe, in one race.
The main race of the event is the 42-km marathon which will set for at 09.00 EET. The race will start 300 metres behind the Bosphorus Bridge before finalizing at an avenue in historical Sultanahmet district.
The 15-km and 10-km races will also start at 09.00 EET.
The public walk will set out at 09.30, covering a course starting from the Altunizade district on the Asian side before procession through the Bosphorus Bridge and ending at Dolmabahce on the European side.
The marathon's guest of honour this year is Elvan Abeylegesse, the Ethiopian-born Turkish athlete, who was the former world-record holder for 5,000 m.
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