Hajdú–Bihar County Hajdú-Bihar vármegye
Counties of Hungary
Descending, from top: Nine-holed Bridge, Herd of Racka sheep in Hortobágy, and Downtown of Debrecen
Flag Coat of arms
Hajdú-Bihar County within Hungary
Country	Hungary
Region	Northern Great Plain
County seat	Debrecen
Districts	10 districts Balmazújváros District Berettyóújfalu District Debrecen District Derecske District Hajdúböszörmény District Hajdúhadház District Hajdúnánás District Hajdúszoboszló District Nyíradony District Püspökladány District
Government
• President of the General Assembly	Zoltán Pajna (Fidesz-KDNP)
Area
• Total	6,210.51 km2 (2,397.89 sq mi)
• Rank	4th in Hungary
Population  (2018)
• Total	530,464[1]
• Rank	4th in Hungary
GDP [2]
• Total	HUF 1,348 billion €4.330 billion (2016)
Postal code	40xx – 422x, 4241 – 4243, 425x – 429x
Area code(s)	(+36) 52, 54
ISO 3166 code	HU-HB
Website	hbmo.hu

Hajdú–Bihar (Hungarian: Hajdú-Bihar vármegye, pronounced [ˈhɒjduː ˈbihɒr]) is an administrative county (comitatus or vármegye) in eastern Hungary, on the border with Romania. It shares borders with the Hungarian counties Szabolcs-Szatmár-Bereg, Borsod–Abaúj–Zemplén, Jász–Nagykun–Szolnok and Békés. The capital of Hajdú-Bihar county is Debrecen. Together with Bihor County in Romania it constitutes the Biharia Euroregion.

The area of the county does not form a geographical unit; it shares several features with the neighbouring areas: from northeast the sand hills of the Nyírség spread over the county borders. The western part is the Hortobágy National Park ("Puszta"), a large flat area of the country. The county of Hajdú–Bihar occupies the eastern part of Hungary. Most of its territory is completely flat and is part of the Pannonian Plain region (called the Grand Plain in the country). The highest point hardly rises over 170.5 metres in the north. It seems that the county slopes to the south because the lowest point is situated in this part of Hajdú-Bihar and hits the 85 metres height.^{[citation needed]}

The wind and rivers formed and shaped the land for thousands of years. First the area of the present-day Hungary was occupied by an inland sea. Then, after some underground movement, the huge peaks of the Carpathians rose from this sea. The wild and rapid rivers of the mountains slowly made that inland sea disappear. Later, the great Hungarian plain was formed by the alluvial deposits of the rivers, the wind began to work and from the great rocks became smaller and smaller sand-grains, the so-called loess. This covers thickly the Hajdú-Bihar plain as well and makes a fertile soil. There are two great rivers in this area, the Tisza and the Körös. The Hortobágy area was formed by the first one. It used to be the flood area of the Tisza river and after the river was controlled, the Hortobágy became dry, resulting in special fauna.^{[citation needed]}

Hajdú–Bihar county was created after World War II from the pre-1938 counties Hajdú and Bihar. See the articles of those counties for the history before World War II.^{[citation needed]}

In 2015, it had a population of 537,268 and the population density was 87/km².

Year	County population[3]	Change
1949	498,271	n/a
1960	522,787	4.92%
1970	524,952	0.41%
1980	551,448	5.05%
1990	548,728	-0.49%
2001	552,998 (record)	0.78%
2011	546,721	-1.34%
2015	537,268	-1.75%
2018	530,464	-1.28%

The main minority populations in the county are Roma (about 18,000), Romanian (about 2,000), and German (about 1,000).^{[citation needed]}

Total population (2011 census): 546,721
Ethnic groups (2011 census):^[4]

• Hungarians: 461,809 (95.05%)
• Romani: 18,132 (3.73%)
• Others and indefinable: 5,936 (1.22%)

About 77,000 people in Hajdú-Bihar County did not declare their ethnicity during the 2011 census.

Religious adherence in the county according to 2011 census:^[5]

• Reformed – 158,513;
• Catholic – 86,084 (Roman Catholic – 53,697; Greek Catholic – 32,359);
• Evangelical – 1,086;
• Orthodox – 862;
• other religions – 10,330;
• Non-religious – 147,001;
• Atheism – 6,416;
• Undeclared – 136,429.

Highways no. 4, 33, 35, 42 and 47 lead to the county and the county can also be reached Hajdú–Bihar via the M3 motorway (this motorway is now a spur to Debrecen). The total length of the public roads in the county is 1,511 km. 122 road bridges span the rivers and canals. The roads cross the national borders to Romania at the cities of Ártánd and Nyírábrány.

The Hajdú–Bihar County Council, elected at the 2024 local government elections,^[6] is made up of 24 counselors,^[7] with the following party composition:

The following members elected of the National Assembly during the 2022 parliamentary election:^[9]

Hajdú–Bihar County has 1 urban county, 20 towns, 10 large villages and 51 villages. Hajdú–Bihar has a comparatively small number of inhabited places: 21 towns and 61 villages. The four largest cities – both by area and by population – are Debrecen, Hajdúböszörmény, Hajdúnánás and Hajdúszoboszló.^{[citation needed]}

City with county rights

(ordered by population, as of 2011 census)

• Debrecen (211,320) – county seat

Towns

Villages

municipalities are large villages.

• 
  Debrecen, the Calvinist Rome
• 
  Pool in Hajdúszoboszló
• 
  Greek Cathedral of Hajdúdorog
• 
  Bocskai Mansion in Nagykereki
• 
  Hungarian grey cattle on the Hortobágy
• 
  University of Debrecen
• 
  Traditional house in Biharnagybajom

Hajdú-Bihar County has a partnership relationship with:^[10][11]

• Official site in Hungarian
• Hajdú Online (haon.hu) – The county portal
• (in Hungarian) Restaurants, bars, pubs, gastro-articles, daily menus from Hajdú-Bihar

47°25′N 21°30′E / 47.417°N 21.500°E / 47.417; 21.500