Split-Dalmatia County is the largest Croatian county with a total area of 14 106.40 km2 where the sea covers a surface area of 9 576.40 km2. Most of the land area consists of the hinterland (59.88%), while the islands make up a lower proportion of the land surface area (19%). Geographically it is located in the central part of the Adriatic coast. The county is divided into three geographical subunits: coastal area, islands and hinterland. The coastal area makes a narrow strip along the coast between the mountain ranges and the sea. This area is highly urbanized and economically developed compared to the hinterland.
The islands are sparsely populated, economically more developed than the hinterland; however, due to various circumstances, they have experienced permanent emigration of the population. The island area of the county is made up of 74 islands and 57 islets and reefs. The hinterland, in the continental part of the county, is crisscrossed by mountains that run parallel to the coastline. The area is sparsely populated and economically poor.
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