Zagreb, Europe (Croatia) - "12hr Zagreb". Location: Zagreb, Mladost Athletic Stadium. Events: 12-hour ultramarathon (Croatia's 12h men’s and women’s national championships; open race for runners who do not compete in the national championships); 6-hour ultramarathon (Croatia's 6h men’s and women’s national championships; open race for runners who do not compete in the national championships); 12-hour ultramarathon relay (3-member relay, each member runs 4 hours; relays can be woman’s, man’s or mixed; relay members are changing on 4th and 8th hour of race). www.12hr.run/pocetna-en