Serbia is a landlocked country located at the crossroads of Central and Southeastern Europe, covering the central part of the Balkans. Serbia is bordered by Bosnia and Herzegovina, Bulgaria, Croatia, Hungary, Kosovo, Macedonia, Montenegro, and Romania. The geography of Serbia is varied and includes fertile plains, limestone ranges, and in the southeast: the Dinaric Alps and the Carpathian Mountain range. The government system is a republic; the chief of state is the president, and the head of government is the prime minister. Serbia has a mixed economic system in which the presence of the state in the economy is considerable, but there is limited private sector freedom. Serbia is a member of the Central European Free Trade Agreement (CEFTA).