Poland is a country located in the center of the European continent and is currently one of the countries that make up the eastern border of the European Union. In terms of population, Poland ranks fifth in Europe with about 38.5 million inhabitants, of which about 97 percent are Poles. This percentage is significantly contributed by the Second World War, in which Poland lost more than six million inhabitants, more than half of whom were Polish Jews. There are numerous monuments and museums about this suffering. Today's Poland is a modern, energetic country with a rich history and tradition. Many castles and cultural monuments testify to over ten centuries of Polish heritage, and 14 of them are included in the UNESCO World Heritage List.