Bosnian men urge their horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. The annual festival celebrates the centuries old tradition of pulling logs honoring the owners of the strongest horses. Owners of the horses gather from all over Bosnia and beyond, and compete in a show of horse strength. (Photo by Amel Emric/AP Photo)

A Bosnian man urges on his horses to pull logs up a hill during competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

A Bosnian man urges jis horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

Horses pull logs during festival in Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

Bosnians encourage their horses as they pull logs up a the hill during competition in Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

A Bosnian boy ride on a horse before a festival of log pulling in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

Bosnian men urge their horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)

A Bosnian man urges his horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. (Photo by Amel Emric/AP Photo)