Lens (French pronunciation: [lɑ̃s] ; Picard: Linse) is a city in the Pas-de-Calais department in northern France. It is one of the main towns of Hauts-de-France along with Lille, Valenciennes, Amiens, Roubaix, Tourcoing, Arras and Douai. The inhabitants are called Lensois (pronounced [lɑ̃swa]).

Lens belongs to the intercommunality of Lens-Liévin, which consists of 36 communes, with a total population of 242,000. Lens, along with Douai and 65 other communes, forms the agglomeration (unité urbaine) of Douai-Lens, whose population as of 2018 was 504,281.

Lens was initially a fortification from the Norman invasions. In 1180, it was owned by the Count of Flanders, and sovereignty was exercised by the Crown of France. In the 13th century, Lens received a charter from Louis VIII of France, allowing it to become a city. The Flemish razed the city in 1303. Prior to this, the city's population relied on its markets. In 1526, Lens was made part of the Spanish Netherlands under the ownership of the French monarchy, and only passed back to France on 7 November 1659 with the Treaty of the Pyrenees.

In 1849, coal was discovered in Lens after surveys were carried out at Annay, Courrières and Loos-en-Gohelle. This led to the expansion of the city into an important industrial center as part of the Nord-Pas de Calais Mining Basin. The Lens Mining Company was founded in 1852 and experienced large profits. The city, occupied from 1914 to 1918, was largely destroyed in the First World War and its population of 18,000 fell by half. In World War II, the Allies bombarded the city from the air, leaving 500 dead and 1,000 buildings destroyed. A new Hôtel de Ville was erected in 1965.

The last coal mine in Lens closed in 1986. The Nord-Pas de Calais Mining Basin was made a UNESCO Heritage site in 2012, and the Louvre-Lens art museum was opened the same year.

Lens is the site of one of the five campuses of the University of Artois.

The Lens railway station, built in 1927, is served by regional trains towards Lille, Arras, Douai, Dunkirk, Calais and Valenciennes. It is also connected to the TGV network, with high speed trains to Paris. It is served by the Lens-Béthune bus network, with bus services running across Lens and connecting it to nearby towns.

Football club RC Lens plays in the town. Their stadium, Stade Bollaert-Delelis, was used for UEFA Euro 1984, the 1998 FIFA World Cup and UEFA Euro 2016 and the 1999 Rugby World Cup and the 2007 Rugby World Cup.

Historical population

Year Pop. ±% p.a. 1793 2,081 —     1800 2,365 +1.84% 1806 2,316 −0.35% 1821 2,381 +0.18% 1831 2,551 +0.69% 1836 2,645 +0.73% 1841 2,673 +0.21% 1846 2,807 +0.98% 1851 2,796 −0.08% 1856 3,341 +3.63% 1861 4,506 +6.17% 1866 5,738 +4.95% 1872 7,298 +4.09% 1876 9,383 +6.48% 1881 10,515 +2.30% 1886 11,780 +2.30% 1891 13,862 +3.31% 1896 17,227 +4.44%	Year Pop. ±% p.a. 1901 24,370 +7.18% 1906 27,744 +2.63% 1911 31,812 +2.77% 1921 14,259 −7.71% 1926 30,155 +16.16% 1931 33,513 +2.13% 1936 32,730 −0.47% 1946 34,342 +0.48% 1954 40,753 +2.16% 1962 42,590 +0.55% 1968 41,874 −0.28% 1975 40,199 −0.58% 1982 38,244 −0.71% 1990 35,017 −1.10% 1999 36,206 +0.37% 2007 36,011 −0.07% 2012 32,663 −1.93% 2017 31,415 −0.78%
Graphs are unavailable due to technical issues. Updates on reimplementing the Graph extension, which will be known as the Chart extension, can be found on Phabricator and on MediaWiki.org.
Source: EHESS and INSEE (1968-2017)

• 
  East of Pas-de-Calais (Béthune, Lens, Hénin-Beaumont)
• 
  Lens church
• 
  Main shopping district
• 
  One of the many cone-shaped coal tips that litter the landscape near Lens
• 
  The Hôtel de Ville

• Stade Bollaert-Delelis
• Communes of the Pas-de-Calais department
• Category:Counts of Lens
• Institut de génie informatique et industriel

• Official web site (in French)
• Communauté d'Agglomeration of Lens-Liévin (in French)