Nitra (Slovak pronunciation: [ˈɲitra] ; also known by other alternative names) is a city in southwestern Slovakia, situated at the foot of the Zobor Mountain in the Nitra River Valley about 90 km (56 mi) northeast of the country's capital, Bratislava. With a population of about 78,353, it is the fifth-largest city in Slovakia. Nitra stands on varied terrain, which features both rolling hills and vast plains, particularly to the south. Nitra is one of the oldest cities in Slovakia. It was the center of the Principality of Nitra, a duchy of great historic significance. Today, the city serves as the administrative center of Nitra Region (kraj) and Nitra District (okres). Nitra is the agricultural capital of Slovakia due to its long tradition of farming, favorable climate, and geography.