Slovakia is a landlocked country in Central Europe. Neighboring countries include Austria, Czech Republic, Hungary, Poland, and Ukraine. The geography of Slovakia is known for its mountains, with the Carpathian Mountains extending across most of the northern half of the country. The government system is a parliamentary democracy; the chief of state is the president, and the head of government is the prime minister. Slovakia has a mixed economic system in which there is a variety of private freedom, combined with centralized economic planning and government regulation. Slovakia is a member of the European Union (EU).