Nógrád (Nógrád vármegye, ˈnoːɡraːd; Novohradská župa) is a county (vármegye) of Hungary. It sits on the northern edge of Hungary and borders Slovakia. Nógrád county lies in northern Hungary. It shares borders with Slovakia and the Hungarian counties Pest, Heves and Borsod-Abaúj-Zemplén. The capital of Nógrád county is Salgótarján. Its area is 2,544 km2. It is the smallest county by population and the second smallest by area (after Komárom-Esztergom). Nógrád is famous for its historic architecture of ancient Gothic churches and stone castles dated to the 13th century. Some historic landmarks includes the Salgó Castle and several baroque buildings constructed in the 18th century and the Vay, Teleki. Much of the northern border of the county is formed by the river Ipoly. The mountain ranges Börzsöny, Cserhát and Mátra lie partly in the county. Due to the mountains, the county is characterised by small villages nestled in the valleys. The two largest settlements are Balassagyarmat, the former county seat, and Salgótarján, which has become a center of industry in the early 20th century due to coal mines nearby. Nógrád County (former) Nógrád (-Hungarian, in Latin: comitatus Neogradiensis, in German: Neuburg or Neograd, in Slovak: Novohrad) was also the name of a historic administrative county (comitatus) of the Kingdom of Hungary. The name stems from the former Nógrád castle (Novohrad - this name is still used in Slovakia as well as the informal designation of the corresponding territory, now located in southern Slovakia and in northern Hungary). Demographics of Hungary In 2015, it had a population of 195,923 and the population density was 77/km2. Besides the Hungarian majority, the main minorities are the Roma (approx. 15,000), Slovak (2,500) and German (1,000). Total population (2011 census): 202,427 Ethnic groups (2011 census): Identified themselves: 192,438 persons: Hungarians: 172,946 (89.87%) Gypsies: 15.177 (7.89%) Slovaks: 2,644 (1.37%) Others and indefinable: 1,671 (0.87%) Approx.