Essonne

Essonne is a department of France in the Île-de-France region. It occupies the southern part of the Paris metropolitan area and also contains extensive rural territory farther south. The department takes its name from the Essonne River and carries the INSEE department number 91. Its prefecture and largest commune is Évry-Courcouronnes. The department was established on 1 January 1968 as part of the administrative reorganization that divided the former Seine-et-Oise department into several smaller departments. Its territory combines densely urbanized communes integrated into the Parisian agglomeration with agricultural landscapes, woodland, historic estates, and smaller rural settlements. Essonne borders Hauts-de-Seine and Val-de-Marne to the north, Seine-et-Marne to the east, Loiret to the south, and Eure-et-Loir and Yvelines to the west. Essonne is both a residential and economic area. Major urban communes include Évry-Courcouronnes, Athis-Mons, Sainte-Geneviève-des-Bois, Vigneux-sur-Seine, Ris-Orangis, Viry-Châtillon, Draveil, Yerres, Étampes, Grigny, Brétigny-sur-Orge, Les Ulis, and Brunoy. In 2023, the department had approximately 1.34 million inhabitants distributed among 194 communes. Its northern section benefits from proximity to Paris and includes significant higher-education, technology, research, transport, and business activity. The department has notable scientific and educational institutions, including École Polytechnique at Palaiseau, Paris-Saclay-related academic facilities in the Orsay and Palaiseau area, and Telecom SudParis in Évry. It is also associated with the headquarters of Arianespace, reflecting the wider aerospace and technology ecosystem of southern Île-de-France. Other landmarks include the Château de Montlhéry, Château de Courances, the Forest of Sénart, and the commercial site in Sainte-Geneviève-des-Bois where Carrefour opened an early Paris-region hypermarket in 1963. Essonne is governed as a French departmental authority within the national and regional administrative structure. Its responsibilities include areas such as social services, departmental roads, certain educational facilities, and territorial development. The department is also connected internationally through a twinning relationship with Ibaraki Prefecture in Japan, established in 1986.

Essonne's modern administrative history begins with the restructuring of the Paris-region departments after the Second World War. The department was created on 1 January 1968 from the southern part of Seine-et-Oise, a former department whose extensive territory was divided to create a more manageable administrative map around Paris. Essonne therefore belongs to the generation of departments established during the reorganization of the Île-de-France area. The department's number, 91, reflects its position in the national departmental numbering system rather than its date of creation. The new department inherited a territory with two distinct geographic and social characters. The north was increasingly absorbed into the Paris metropolitan area, with growing housing, transport infrastructure, industry, and suburban commercial development. The south retained agricultural land, villages, forests, historic estates, and a more rural settlement pattern. This contrast has remained central to Essonne's identity and to the public policies required from its departmental authority. The area also became an important location for modern retail. In June 1963, Carrefour opened an early hypermarket at Sainte-Geneviève-des-Bois. The site combined a broad product assortment, low prices, and extensive automobile parking on a large-format retail site. It is widely regarded as the first Carrefour hypermarket in the Paris region and as an important early example of the hypermarket model. Although the French word for hypermarket was not coined until later, the Sainte-Geneviève-des-Bois store illustrated the emerging relationship between suburban development, mass automobile ownership, centralized retail distribution, and consumer choice. In 1969, the communes of Châteaufort and Toussus-le-Noble were transferred from Essonne to the neighboring department of Yvelines. This adjustment followed the department's creation and helped refine the administrative boundaries of the Paris region. During the second half of the twentieth century, northern and central Essonne developed major educational and scientific functions. Palaiseau became associated with École Polytechnique, while Orsay and the wider Paris-Saclay area developed strong university and research capabilities. Évry became an administrative and higher-education center, including Telecom SudParis. The presence of Arianespace's headquarters further connected the department with France's aerospace and satellite-launch sector. The department's built and natural heritage includes the medieval Château de Montlhéry, whose origins reach back to Roman-era occupation and early feudal settlement; Château de Courances; and the Forest of Sénart. The latter covers about 3,500 hectares and is heavily used for recreation, receiving an estimated two to three million visitors annually. Local authorities have sought to protect the forest from excessive development and have maintained its paths and surrounding environmental resources. Politically, Essonne has produced nationally prominent figures. Manuel Valls, who represented the department politically and later served as Prime Minister of France from 2014 to 2016, is among its best-known associated figures. The department is administered through its prefecture in Évry-Courcouronnes and its elected Departmental Council. Its contemporary role combines metropolitan governance, social and infrastructure services, economic development, environmental stewardship, and support for a territory that ranges from dense urban districts to rural communes such as Milly-la-Forêt. Essonne also maintains an international relationship with Ibaraki Prefecture in Japan, with the twinning dating from 1986. This relationship forms part of the department's external cultural and institutional links.

• 2023

  Population recorded at 1,338,485

  [1]Essonneen.wikipedia.org

  Essonne's population was reported at 1,338,485 residents across 194 communes.

• 2015

  François Durovray becomes president of the Departmental Council

  [1]Essonneen.wikipedia.org

  François Durovray was elected president of the Essonne Departmental Council.

• 1986

  Twinning with Ibaraki Prefecture

  [1]Essonneen.wikipedia.org

  Essonne established a sister-region relationship with Ibaraki Prefecture in Japan.

• 1969

  Two communes are transferred to Yvelines

  [1]Essonneen.wikipedia.org

  Châteaufort and Toussus-le-Noble were separated from Essonne and incorporated into Yvelines.

• 1968

  Essonne is established as a department

  [1]Essonneen.wikipedia.org

  Essonne was created on 1 January from the southern portion of the former Seine-et-Oise department.

• 1963

  Carrefour opens an early Paris-region hypermarket

  [1]Essonneen.wikipedia.org

  Carrefour opened a large-format store in Sainte-Geneviève-des-Bois, an important early example of the hypermarket model in the Paris region.

A diversified southern Île-de-France department combining Paris metropolitan urbanism, research and technology assets, transport-linked economic activity, and protected rural and cultural landscapes.

• Public administration · 1968

  Departmental public services

  Essonne's principal output is public administration rather than commercial goods. Through its departmental institutions, it provides territorial services associated with social support, departmental infrastructure, public facilities, local development, and the management or protection of parts of its environmental and cultural heritage.

• Education and research

  Research and higher education

  The Palaiseau, Orsay, and Évry areas host important higher-education and research institutions. École Polytechnique, Paris-Sud University facilities, and Telecom SudParis contribute to Essonne's profile as a science, engineering, and technology territory within the Paris-Saclay ecosystem.

• Aerospace

  Aerospace and satellite-launch activity

  Essonne is associated with the headquarters of Arianespace, a major commercial space-launch company. This presence links the department to the wider French and European aerospace sector and complements its concentration of technical education and research.

• Tourism and heritage

  Cultural and natural tourism

  The department's tourism and heritage offer includes Château de Montlhéry, Château de Courances, the Forest of Sénart, and the rural landscapes around communes such as Milly-la-Forêt. These assets provide historic, recreational, and environmental attractions close to the Paris metropolitan area.

• 1969

  Boundary adjustment with YvelinesStrategy

  Background

  The boundaries of the newly created Paris-region departments were refined after the 1968 reorganization.

  Action taken

  Châteaufort and Toussus-le-Noble were transferred from Essonne to Yvelines.

  Aftermath

  The change established the departments' subsequent territorial arrangement in this area.

  Source

• 1968

  Creation of a separate Essonne departmentStrategy

  Background

  The French state reorganized the Paris-region administrative structure by dividing the former Seine-et-Oise department.

  Action taken

  The southern portion of Seine-et-Oise became the new department of Essonne on 1 January 1968.

  Aftermath

  Essonne developed as a distinct departmental authority encompassing both southern Paris suburbs and rural territory.

  Source

1. 1Essonneen.wikipedia.org
2. 2Prefecture of Essonneessonne.pref.gouv.fr