Croatia, officially the Republic of Croatia, is a country at the crossroads of Central and Southeast Europe on the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, and Bosnia and Herzegovina and Montenegro to the southeast, and it shares a maritime border with Italy.
Tourism accounts for 20% of the Croatian GPD. The bulk of the tourist industry is concentrated along the Adriatic Sea coast. Opatija was the first holiday resort. It first became popular in the middle of the 19th century. By the 1890s, it had become one of the most significant European health resorts. Later a number of resorts sprang up along the coast and islands, offering services catering to both mass tourism and various niche markets. The most significant are nautical tourism, as there are numerous marinas with more than 16 thousand berths, cultural tourism relying on the appeal of medieval coastal cities and numerous cultural events taking place during the summer. Inland areas offer agrotourism, mountain resorts, and spas. Zagreb is also a significant tourist destination, rivalling major coastal cities and resorts.
Croatia has unpolluted marine areas reflected through numerous nature reserves and 116 Blue Flag beaches. Croatia is ranked as the 23rd most popular tourist destination in the world. About 15% of these visitors, or over one million per year, are involved with naturism, an industry for which Croatia is world-famous. It was also the first European country to develop commercial naturist resorts.
The Plitvice Lakes National Park is the oldest and largest national park in the Republic of Croatia, famous for its numerous turquoise-coloured lakes separated by tufa, or travertine, barriers. Its karst landscape is characterised by specific hydrological traits and exceptional biological diversity, which helped the National Park gain international significance.