Wittenberg's UNESCO World Heritage Site is recognized for its significant role in the Protestant Reformation. It includes important landmarks such as the Castle Church, where Martin Luther famously posted his Ninety-Five Theses in 1517, challenging the practices of the Catholic Church. The site also features the Luther House, which served as Luther's residence and a center for Reformation activities. Together, these sites reflect the historical and cultural importance of Wittenberg in shaping modern Christianity and European history.