Lengnau is a municipality in the Biel/Bienne administrative district in the canton of Bern in Switzerland.

[3] The oldest traces of humans are late-paleolithic to neolithic flint tools and other objects which were discovered on the Aare river plain.

During the Middle Ages it was part of the Herrschaft of Strassberg, which was acquired by Bern in 1388-93.

In 1318, during a conflict between Solothurn and Habsburg Austria the village and its church were burned.

The Jura water correction projects of the 19th century, drained much of the previously unusable Aare flood plain and opened up extensive agricultural land in Lengnau.

During the same time, Lengnau began to develop from a farming village into a watch making town with industries.

In addition to watchmakers, other industries, such as timber cutters and engineering firms opened in town.

Despite the establishment of new industries in 1983, including; precision machines, electronics companies and décolletage, many workers commute to jobs in other towns.

A train station on the Olten-Biel line opened in Lengnau in 1857 and a branch to Moutier was added in 1915.

[5] The municipality is located at the foot of the Jura Mountains in the Aare river plains.

[6] The blazon of the municipal coat of arms is Argent a Fir tree Vert trunked Gules issuant from a Mount of 3 Coupeaux of the second.

[10] Most of the population (as of 2000[update]) speaks German (3,914 or 87.8%) as their first language, French is the second most common (116 or 2.6%) and Italian is the third (103 or 2.3%).

The historical population is given in the following chart:[3][13] In the 2011 federal election the most popular party was the SVP which received 31.2% of the vote.

The number of jobs in the primary sector was 23, of which 19 were in agriculture and 3 were in forestry or lumber production.

In the tertiary sector; 134 or 31.7% were in wholesale or retail sales or the repair of motor vehicles, 25 or 5.9% were in a hotel or restaurant, 10 or 2.4% were in the information industry, 11 or 2.6% were the insurance or financial industry, 28 or 6.6% were technical professionals or scientists, 66 or 15.6% were in education and 72 or 17.0% were in health care.

[10] From the 2000 census[update], 732 or 16.4% were Roman Catholic, while 2,711 or 60.8% belonged to the Swiss Reformed Church.

This is followed by three years of obligatory lower Secondary school where the students are separated according to ability and aptitude.

Following the lower Secondary students may attend additional schooling or they may enter an apprenticeship.