Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe, situated on the Balkan Peninsula. It borders Serbia to the east, Montenegro to the southeast, and Croatia to the north and southwest. In the south it has a 20 kilometres long coast on the Adriatic Sea, with the town of Neum being its only access to the sea. Bosnia has a moderate continental climate with hot summers and cold, snowy winters. In the central and eastern regions, the geography is mountainous, in the northwest it is moderately hilly, and in the northeast it is predominantly flat. Herzegovina, the smaller, southern region, has a Mediterranean climate and is mostly mountainous. Sarajevo is the capital and the largest city.