<prompt> Translate the following text to EnglishWakati wa utawala wa Ferdinand na Isabella, umoja wa Hispania ulifikiwa na Kristo Kristo Columbus akaanza safari ya kwenda Amerika mwaka 1492.  <response>: Under Ferdinand and Isabella, the unity of Spain as the country we know today was finally achieved, and it was carrying their flag that in 1492 Christopher Columbus sailed westwards and discovered America. 