Zagreb is the capital and largest city of Croatia.It is in the northwest of the country, along the Sava river, at the southern slopes of the Medvednica mountain. Zagreb stands near the international border between Croatia and Slovenia at an elevation of approximately 122 m  above sea level. The population of the Zagreb urban agglomeration is 1,071,150, approximately a quarter of the total population of Croatia

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Zagreb is a city with a rich history dating from Roman times. The oldest settlement in the vicinity of the city was the Roman Andautonia. The historical record of the name "Zagreb" dates from 1134, in reference to the foundation of the settlement at Kaptol in 1094. Zagreb became a free royal city in 1242.

The city has many open squares and parks. As the cultural centre of Croatia, Zagreb is the seat of the Academy of Sciences and Arts and of the University of Zagreb (1669). Several art galleries have both old and modern collections, and there are various museums and academies of art, theatre, and music. The Croatian National Theatre is housed in a neo-Baroque building in the city.

for more information you can visit official web site of Zagreb