The purpose of such colleges is to bring young people from different religious and national backgrounds closer through the process of education, the opening ceremony heard.
Sixty-six students from 19 countries, including Croatia, attend Mostar's UWC, which actually began classes in last September.
Addressing the ceremony, Queen Noor said that the Mostar college would help the young people better understand each other and that skills developed at such colleges would eventually contribute to peace in the world.
Queen Noor is the president of the network of United World Colleges.