The humanitarian race is organised by the Canadian Embassy in Croatia in cooperation with the Croatian Anti-Cancer League.
The event was held under the auspices of Croatian Health and Social Welfare Minister Andrija Hebrang and the wife of President Stjepan Mesic, Milka.
Last year the race raised 150,000 kuna, while this year organisers expect to raise twice that amount.
Canadian Ambassador to Croatia Stefanie Beck last week called on Zagreb's residents to take part in the race.
(EUR1 = 7.4 kuna)