Nitra (nyĭˈträ) [key], Ger. Neutra, Hung. Nyitra, city (1991 pop. 89,969), W Slovakia, on the Nitra River, a tributary of the Danube. It is an agricultural market center and has extensive food-processing industries. Dating from Roman times, Nitra was important from the 9th cent. onward as a religious center and fortress. It became a free city by royal decree in 1248 and was made a Roman Catholic bishopric in 1288. Nitra's bishopric church and a castle (founded c.830) are the oldest structures in Slovakia. The city also has an agricultural college.