Undervelier is a former municipality in the district of Delémont in the canton of Jura in Switzerland.

[4] The former municipality is located in the Delemont district, between two of the Sorne river canyons and at the foot of Pichoux mountain.

The blazon of the municipal coat of arms is Or three Piles issuant from sinister shortened Sable.

[8] Most of the population (as of 2000[update]) speaks French (258 or 80.4%) as their first language, German is the second most common (49 or 15.3%) and Italian is the third (7 or 2.2%).

[8] The historical population is given in the following chart:[2][12] The entire Les Forges area is designated as part of the Inventory of Swiss Heritage Sites.

[13] Notable sights in the area include the cave of Sainte-Colombe and the Gorges of Pichoux.

Other sights include the Vellerat Posé because of its greenery and the chapel Place Roland Béguelin built by Jeanne Bueche and André Bréchet's stained glass windows.

[8] There were 129 residents of the municipality who were employed in some capacity, of which females made up 38.0% of the workforce.

The number of jobs in the primary sector was 29, of which 28 were in agriculture and 1 was in forestry or lumber production.

In the tertiary sector; 3 or 37.5% were in wholesale or retail sales or the repair of motor vehicles, 2 or 25.0% were in a hotel or restaurant, 1 was in the information industry, and 1 was a technical professional or scientist.

[8] From the 2000 census[update], 186 or 57.9% were Roman Catholic, while 51 or 15.9% 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.