A landlocked country in Central Europe, Austria's two main geographic features are the Alps - which give the country its mountainous landscape - and the Danube river - which flows through Austria's north on its way to the Black Sea. An important avenue for Austrian trade with Central and Eastern Europe, the Danube also runs through the country's capital city of Vienna. Austria has traditionally been a Central European power, with areas of influence ranging from the Carpathians in the east to the Balkans in the south. From the 13th to the early 20th century, the Austrian Habsburg monarchy was a major political player in Europe. Though the Allies occupied Austria after World War II, the country managed regain full independence in 1955 after declaring neutrality. This allowed Vienna to position itself as bridge between the Soviet Union and the West during the Cold War. To this day, Austria remains a meeting point for world leaders and contains the headquarters of many international organizations. Though Austrian influence over European affairs has diminished significantly since the end of the Hapsburg monarchy, the country joined the European in 1995 and still considers itself an interlocutor between Eastern and Western Europe. Austria has sought to rebuild its traditional sphere of influence over the territories that were once part of its empire, particularly through investment. As an export-oriented country, Austria is supportive of the European Union as long as it creates opportunities for trade and investment. However, Austria is not a founding member of the European project and is skeptical of the process of EU integration. Austria's main geopolitical challenge is therefore to preserve ties with its neighbors without jeopardizing its national sovereignty.