Croatia, officially the Republic of Croatia, is a country in Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herzegovina and Montenegro to the southeast, and shares a maritime border with Italy to the west. The Croatian archipelago contains over 1,000 islands and islets, the largest overseas territory on the Adriatic Sea. Its capital, largest city and main cultural and economic centre is Zagreb. Major urban centers include Split, Rijeka, and Osijek. The country is composed of twenty counties spanning 56,594 square kilometres within four administrative regions. Croatia has a population of nearly 3.9 million as of 2026.