Croatia [ˌkɹoʊˈeɪʃə] (Croatian: Hrvatska IPA: [ˈxȓ.vat.ska]), officially the Republic of Croatia (Republika Hrvatska listen (help·info)), is a southern Central European country at the crossroads between the Pannonian Plain and the Mediterranean Sea. Its capital is Zagreb. Croatia borders with Slovenia and Hungary to the north, Serbia to the northeast, Bosnia and Herzegovina to the east, and Montenegro to the far southeast. Its southern and western flanks border the Adriatic Sea, and it also shares a sea border with Italy in the Gulf of Trieste. Croatia is a member of the United Nations, the Organization for Security and Co-operation in Europe and the Council of Europe. The country is also a candidate for membership of the European Union and received a NATO membership invitation on April 3, 2008. NATO member nations signed accession protocols for Croatia on July 9, 2008, bringing it into the final stretch of its quest for membership. Croatia is expected to formally join the 26-nation pact in April 2009 on NATO's 60th birthday, making it the second former Yugoslav nation to join NATO following Slovenia which entered in 2004. On October 17, 2007 Croatia became a non-permanent member of the United Nations Security Council for the 2008-2009 term. Additionally, Croatia is also a founding member of the Mediterranean Union upon its establishment on July 13, 2008. Croatia is located between South-Central Europe and Middle Europe. Its shape resembles that of a crescent or a horseshoe, which flanks its neighbours Serbia, Bosnia and Herzegovina and Montenegro. To the north lie Slovenia and Hungary; Italy lies across the Adriatic Sea. Its mainland territory is split in two non-contiguous parts by the short coastline of Bosnia and Herzegovina around Neum. The country is famous for its many national parks. Croatia has a mixture of climates. In the north and east it is continental, Mediterranean along the coast and a semi-highland and highland climate in the south-central region. Offshore Croatia consists of over one thousand islands varying in size. The largest islands in Croatia are Cres and Krk which are located in the Adriatic Sea. The Danube, Europe's second longest river, runs through the city of Vukovar. Dinara, the eponym of the Dinaric Alps, is the highest peak of Croatia at 1,831 metres above sea level.